Monday, April 27, 2020

Jesus de la Villa: 100 endgames you should know

Jesus de la Villa: 100 endgames you should know

A book about endgames.... Who buys that? And more important who reads such thing from cover to cover? The answer is simple: the player really eager to improve.

But then there also "good" and "bad" books about endgames like you have good and bad books about openings and the middlegame. What distinguishes now the book of De La Villa from other endgame-books? I will compare mainly with Nunn’s 100 Endgames, but also some other endgame-books (and their approach) will be covered.

The main asset of de la Villa’s book is that it is well structured and has a format of lessons connected per theme. It is built from the beginning till the end as a textbook, contrary to others which try to be complete. I like this as other (older) endgame-books miss often this thematic approach. It is much easier for the student to digest the content split in lessons of about the same size with their unique theme. Also good are the rules of thumb given in every lesson. You want the strategy explained in simple rules and not too technical with e.g zones drawn on the board which tell you when it is won/ drawn (as nobody can remember such theory). In other books you often get lost in too large chapters, with no refined content. Often you also feel jumping from one type of position/ material to another.

One example: when you are defending (with white) the endgame K+R vs K+R+f-&h-pawn we are told that the defending rook is best positioned in the "northwest corner (so around square a8). This was the very first time that I read somewhere this simple rule - it is no guarantee to draw - but just knowing it can improve your odds. This book is full of those easy to remember rules.

Also nice is that the book puts priority at the most common reached endgames. Often these are endgames of maximum 6 pieces on the board. Rook-endgames are considered as the most important ones which is no surprise. However the opposite bishop-endgames of K+B+2p vs K+B are second which is maybe less trivial. Besides this is just the endgame of which I had some first hand experience.

A nice supplement are the short exercises which are presented each time after some lessons. Sometimes the task is doubled by asking the question how to play the position with white/black when the pieces are moved 1 column on the board to the right or left. 

As we have now all 7-piece endgames (Lomonosov and since beginning of 2020 also Chessbase), it is possible to practice them against perfect play (highly recommended). We are now having apps available for it as our current engines are very strong but not perfect yet.

A disadvantage - but at the same time also an advantage - is that it is a light book. It is not an endgame-encyclopedia, in other words the examples and exercises are limited to the bare minimum, which also means every exercise counts. Are there some real gaps in this book? Almost none but I still want to mention a few smaller ones.

A first critic is that in the first exercises there are some endgames about themes which aren't yet discussed. This seems to me a rather evident mistake which could've been avoided easily.

A second - much smaller critic is that the courses are sometimes deviating quite a bit of size. It is logical that some themes need to be explored more deeply but for people willing to finish 1 per day then it is annoying that sometimes you are finished in 15 minutes and other times only after more than a half hour. I think Nunn's 100 has more discipline with each time 2 full pages (often 4 positions) per item. However at the other hand I didn't have a problem to finish 1 theme per day in De la Villa which wasn't always the case with Nunn as his pages were often more filled (so heavier stuff to study).

A third - and more relevant critic is that there are some real mistakes in this book. As you can check nowadays endgames with the tablebases it is rather easy to detect some evaluations are wrong - especially in the exercises at the end of the book. It also happens some lines are wrongly evaluated but those are real exceptions.

A comparison with other more general books of endgames isn't so easy for me as I don't have many other general ones. I even had to look at one of my classics: Euwe’s Practical lessons part 4. After rereading it, I had to admit that Euwe was also a very good teacher and his evaluations were of a very high standard, so he could match De La Villa. I only consider De La Villa a bit better structured and easier to study (as he uses 100 easy chapters). So it was a close call. The comparison with the double of Cheron can't be made as Cheron is of another level and much more complete. Cheron is many times more serious analysis (definitely not to be used for training). Also the endgame-bible of Muller is not for training but more a detailed summary of the different endgame-categories. So you use this more as a reference to search a special endgame. Another real training-book is the Polgar's endgame-bible. However that is a book of just 4560 positions which are pure training without any explanations so didactically from a lower level. And Silmans Silmans Complete Endgame Guide is rather for the (absolute) beginner.

It is hard to compare with specific endgame-books (which focus on pawn- or rook-endgames) as they are specialized in it like Secrets of Pawn Endings, or Averbakhs / Nunns books about rook-endgames. But even then I still like De la Villa’s 100 EYMK as it is well structured and balanced. It is more profitable to have a few clear rules of thumb than have dozens of examples worked out in detail (it is easy to be overwhelmed).

In the interrupted candidates of 2020 one position from the book popped up in round 1 (Giri vs Nepomniachtchi). I also experienced once such moment: I lost a very difficult opposite bishop-endgame and had to wait till the 6-piece endgame became available to know the truth (as even the engines to day still make mistakes in it). I talk about the game shown below:
[Event "IC4A0708 Doornik vs TW"] [Site "?"] [Date "2007.11.04"] [Round "3"] [White "Minet, Julien"] [Black "HK5000"] [Result "1-0"] [SetUp "1"] [FEN "2B5/5ppp/2k5/bpB5/3P2PP/3n4/PP3P2/6K1 w - - 0 40"] [ECO "B22"] [PlyCount "75"] [EventDate "2007.??.??"] [EventType "game"] {After the failed opening of black we reached move 40. Black decides that his best chance is an endgame of opposite bishops (probably right) but the question is where should the pawns be put} 40. Bf5 {It is bit weird white agrees for the endgame of opposite bishops but maybe time played a role.} 40... Nxc5 41. dxc5 {And now: g6 or h6? A first important key-moment in this endgame. Black chose:} 41... g6? {which isn't the best for different reasons which aren't always justified: black wins another tempo and limits the scope of the white bishop while not hampering its own bishop.} (41... h6 {this would be sufficient for a draw.} 42. a3 (42. Kg2 Kxc5 43. Bd7 Bd8 44. h5 Bf6 45. Be8 Bxb2 46. Bxf7) 42... b4 (42... Bd2 43. b3 Kxc5 44. h5 Bc1 45. a4 bxa4 46. bxa4 Kb4) 43. a4 (43. Bh7 Kxc5 44. Bg8 bxa3 45. bxa3 Kb5 46. Bxf7 Ka4 47. Kg2 Bd8 48. Kg3 Kxa3 49. f4 Kb4 50. g5 Kc5 51. Kg4 Kd4 52. Be6 Ke4 53. Bf5+ Ke3 54. Bg6 Bc7 55. f5 hxg5 56. hxg5 =) (43. axb4 Bxb4 44. g5 (44. Kg2 Kxc5) 44... hxg5 45. hxg5 Kxc5 =) 43... b3 44. Bh7 Kxc5 =) 42. Bc2 Kxc5 43. g5! {I had seen that I could return with the king but it wouldn't solve all the weaknesses. Therefore I prefer to march forward.} 43... Kd4 44. Bb3 Ke5 45. Bxf7 Kf4 46. Bg8 Kg4 47. Bxh7 Kxh4 48. Bxg6 Kxg5 {Now it is 3 against 1. White still needs to demonstrate his technique.} 49. Be8 b4 50. Kf1 Bb6 51. Ke2 Bd4 52. a3 Bxb2 53. axb4 {Draw says Lomonosov.} 53... Bd4 (53... Bc3 54. b5 Bd4 55. f3 Kf4 56. Kd3 Bf2 57. Bc6 Ke5 58. Kc4) 54. f3 Kf4?? {And this is the decisive mistake according to Lomonsov. The engines have still difficulties to find the strongest moves. Bc3 is the only move still making a draw.!} (54... Bc3! 55. b5 Kf4 {Only now and the single move which holds the draw.} (55... Bd4 56. Kd3 Bb6 57. Ke4) 56. b6 Ba5 57. b7 Bc7 58. Bf7 =) 55. Kd3 Bf2 56. Bh5 Ke5 57. Kc4 Kd6 58. Kb5 Be3 59. Ka6 Kc7 60. Bg6 Kb8 61. b5 Kc7 62. Be4 Kb8 63. b6 Bf4 64. Kb5 Be3 65. Kc6 Kc8 66. b7+ Kb8 67. Kd7 Bf4 68. Ke6 Kc7 69. Kf5 Bd6 70. f4 Kd7 71. Kg5 Ke7 72. Bd5 Kf8 73. f5 Be5 74. Kg6 Ke7 75. f6+ Kf8 76. Kf5 Bb8 77. Ke6 +- 1-0
You can find almost an exact copy of this endgame in the book: Position 9.17 (a study of Speelman, the most unfavorable version of this endgame), but also as Position 2.09:

with the question: is this a draw (white to move). The answer is yes as the bishop can stop both pawns on the same diagonal. It looks impossible but the black king does block the white king: 1.Bc8 Bh2 2.Kd5 Kf6 3.Kc6 Ke7 4.Kb6 Bb8! 5.Bg4 Kd6 6.Bh3 Ke7 7.Kc6 Bf4=.

Conclusion: this book will let you improve. Let it be the only endgame-book you buy once every 5 years and read it every year. Success guaranteed!

PS at the top of the article you can also see a picture of the exercise-book. I didn't start yet at it but it are 300 exercises which for sure can be used to train. Anyway just start first with the 40 exercises at the back of this book.


Monday, April 20, 2020

Tactics part 4

I am playing chess for many years and I always wondered how comes players can have so different skills but can still have exactly the same rating. People often ask what needs to be done to obtain rating x but I don't think there exist one firm answer for it. A rating is nothing more or less than the sum of a number of features a person has of which naturally some are more important than others.

Today there also is a lot of doubt about the old rule that chess is 99% tactics. Yes it is wise we first teach to beginners tactics and the steps-books are definitely very useful for it but once the basics are learned progress is much harder. In many Flemish clubs teachers limit their classes to tactics which does after some time slow down their students or worse let them stagnate.

A couple of recent researches prove that there is no strong correlation between elo and tactical skills contrary to common understanding. It was therefore a big disappointment for Jan Gooris to find out via a small inquiry that it isn't so useful to fill Vlaanderen  Schaakt Digitaal with tactical exercises as he was doing for each edition. Of course he could use as excuse that only 10 persons cooperated but it was for sure no good advertisement. (see vsd 2020-03 pdf).

A different angle is shown in 2 more recent scientific papers: Assessing the difficulty of chess tactical problems and A Computational Model for Estimating the Difficulty of Chess Problems.pdf. In first instance they let players solve tactical exercises but the focus is rather at defining the difficulty of the problems. It became clear that fide-elo doesn't say much about how a person looks at a problem. This first study also used the modern eye-tracking-method to discover which parts of the board or which moves were looked at by the players. In the second paper the researchers disregarded the human input as unreliable and tried to build a computer-model for assessing the difficulty of the tactical chess-problems. By checking a list of parameters in the solving-tree it became possible to get an acceptable degree of accuracy. Such algorithm isn't only interesting for chess but can also be used in other domains of course.

Nevertheless many players didn't like it and even criticized the Greek Dimitrios Ladopoulos , having no official chess-title when recently he almost became the world-champion solving tactical problems at despite many strong grandmasters participated. He surely cheated although he was live streaming his performances. He just learned the solutions by heart, as indicated by the candidates-finalist Maxime Vachier-Lagrave in an interview published beginning of this year. Maxime lost their direct duel while being 500 points higher rated than Dimitrios so I guess his must have been very painful especially while many fans were watching live.

On the other hand I should not minimize tactics either. Most games even at my level are still decided by players missing tactics. Any top-grandmaster excels of course in tactics but sometimes you also can meet a player at the lower echelons being very strong at tactics. Twice this season I encountered such person at the other side of the board.

In the first round of the Belgian interclubs I played against the congenial French fide-master Rabah Bouhallel. More than a decade ago I played for his team in Rijsel/Lille so I was very well aware about his fabulous tactical skills especially when he is low on time. It is no coincidence that today Rabah has still a French blitzelo of +2500. So during the game I paid special attention to allocate a time-buffer to avoid playing blitz. I managed to do that till I got a winning position. When I tried in vain to find the knock-out, my extra time evaporated so in the end I still had to play several moves quickly.
[Event "Interclub KOSK - Deurne"] [Site "?"] [Date "2019"] [Round "?"] [White "Bouhallel, R."] [Black "Brabo"] [Result "1-0"] [SetUp "1"] [FEN "5r2/2p2qk1/1n4pp/3np3/7N/P3P1PP/1BQ1R2K/8 b - - 0 38"] [ECO "C44"] [WhiteElo "2305"] [BlackElo "2306"] [PlyCount "2"] 38... Qe6? {(A blunder but I do appreciate how Rabah managed in a couple of seconds to calculate and execute the beautiful combination.)} (38... Nd7! 39. Qc6 g5 40. Ng2 N5f6 41. Rd2 Re8!) 39. Bxe5+ {(Here I lost to my horror on time. This never happened before to me when playing with an increment of 30 seconds per move.)} (39. Bxe5+ Qxe5 {(I played this move a fraction too late but it didn't matter as Rabah showed me immediately the winning tactic.)} 40. Qxg6+ Kh8 41. Qxh6+ Kg8 42. Qxf8+ Kxf8 43. Ng6+ +-) 1-0
It was the very first time that I lost on time while playing with the 30 seconds increment per move (if we ignore my recording error as explained in my article the sadistic exam). In the KOSK it is always a bit awkward to play as they offer beer just a couple of meters away from the players (see also the report of the match from Deurne) but I first didn't realize that I lost on time at move 39. Nor did I realize first that the final position was losing for me as Rabah showed me the winning combination after the game. He had seen everything within seconds while I think it would be probably a not so easy puzzle at

This was nice, very strong but what happens in my second example also played in the Belgian interclubs is something extraordinary. The Belgian IM Stefan Beukema is famous for his extremely complex tactical fights which allowed him to defeat multiple grandmasters. However after our game I was perplexed and therefore asked the question directly to Stefan if this all was planned or just pure luck. "Yes till Qg8 I had calculated it and in the resulting position I saw some great possibilities for white" was the answer of Stefan. I don't think it is important for this story that Stefan had a perfect non tactical alternative and his combination contained a small practically invisible gap.
[Event "Interclub Brasschaat - Deurne"] [Site "?"] [Date "2020"] [Round "?"] [White "Beukema, S"] [Black "Brabo"] [Result "1-0"] [SetUp "1"] [FEN "1rbn1rk1/2qnp1bp/1p3pp1/2p2P2/NPPp2PQ/3P1N2/3BP1BP/R4RK1 b - - 0 17"] [ECO "A03"] [WhiteElo "2420"] [BlackElo "2296"] [PlyCount "32"] 17... e5? {(I learned from my game against the FM Hans Renette with the Bird that black should try to play e5 but this is the wrong moment.)} (17... Bb7! 18. Qg3 Qxg3 19. hxg3 e5 20. Rfb1 Ra8) 18. fxg6 hxg6 19. Ng5? {(I had missed this move. Stefan is a magnificient tactician but after the game I had to ask him if this was all planned. It is not the best move for sure. Qg3 and bxc5 were objectively stronger.)} (19. bxc5!? bxc5 20. Ng5! {(Now this works. Besides also for Leela this is too deep. Stockfish has no problems to dissect the position.)} 20... fxg5 21. Bd5+ Nf7 22. Bxg5 Bb7!? 23. Rxf7 Rxf7 24. Bxf7+ Kxf7 25. Qh7 Nf8?! {(The radical Bf3 defends better.)} 26. Rf1+ Ke8 27. Qg8 Bc8 {(Via a transposition we are back in our game.)}) 19... fxg5 20. Bd5+ Nf7 21. Bxg5 Bb7 22. Rxf7 Rxf7 {(After the game Stefan recommended Bxd5 but that loses immediately after Rxg7.)} (22... Bxd5?? 23. Rxg7+ Kxg7 24. Qh6+ Kg8 (24... Kf7 25. Qh7+ Ke8 26. Qe7#) 25. Qxg6+ Kh8 26. cxd5 +-) 23. Bxf7+ Kxf7 24. Qh7 Nf8 25. Rf1+ Ke8 26. Qg8 Bc8 27. bxc5 bxc5?? {(Probably only an engine can still save this. It doesn't help that I was running out of time.)} (27... Rb7! 28. Nxb6!? Qxc5 29. Nd5 Qd6 30. Nf6+!? Bxf6 31. Rxf6 Qxf6 32. Bxf6 Be6 33. Qh8 Rh7 34. Qxh7 Nxh7 35. Bxe5 Bxg4 36. Kf2 Ng5 37. Bxd4 {(This line is not forced but demonstrates how complex the lines are. Even the resulting endgame is not easy.)}) 28. Nxc5 Rb6 29. Ne4 Be6 30. Rxf8+ {(I also missed this one and this time it finishes the game very quickly. )} 30... Bxf8 31. Nf6+ Ke7 32. Nd5+ Kd7 33. Qh7+ 1-0
I missed several of the keymoves. For sure I would've never dared to play such combination especially when having a safe alternative (see part 1). Leela also can't find the win despite running on my strong new computer. Only Stockfish manages to calculate through the myriad of lines which proofs how difficult the tactics were in the game.

These are splendid combinations but I would rather execute them instead of being on the receiving end. Anyway I don't think that I can ever become so strong at tactics even if I practice every day for many hours. I can better use my time for training other things. Of course it remains important to regularly do a limited number of tactics which can be done by just making the 5 free daily exercises at


Monday, April 13, 2020

Memory part 2

My chess has some serious handicaps as I don't vary sufficiently my openings and also many of those openings can't stand the scrutiny of the current best engines. Therefore I always try to compensate those handicaps by preparing my games very extensively. On the blog I've shown many examples about how I taught myself different techniques to transform the preparation of a game into an ultimate weapon. I guess that many professional players aren't so advanced in that domain. It is a discipline based on a strong organization, hard work and an eternal quest for improvements. In other words most players hate it and I assume this is also the reason why many players wrongly see my preparations as some kind of proof that I posses a very extensive or even absolute opening-knowledge.

It is no surprise that in 90% of my 124 games of which my opponent was aware about my legendary game-preparations, my opponents chose to deviate first from their earlier played games purely to avoid my preparation. So the number of games as discussed in my article novelty seeker part 2 are very rare. I find this a pity as I wrote in a reaction on my article surprises part 3 as the games would be theoretically much more interesting when both players could prepare themselves. I remember one anecdote about 2 players living around Bruges making an agreement to play 1 specific opening but that is the exception on the rule. Most players prefer that the fight happens on the board and aren't interested in the academic evaluations of an opening.

The next question is of course then if my opponents harm themselves by playing something of which they have no experience. Well I have shown in my article the expert that a preparation of a game almost always is stronger than an expert. Nevertheless when looking at my own games, even when my opponents know my blog/ reputation then still 40% doesn't prepare anything at all. Of course there is sometimes very little time but in most cases they don't care. It just proofs once more that many players are extremely lazy but maybe I am too harsh here as probably chess is just another game for them. 

However this also means that 60% of my opponents knowing my reputation, do check at home how they can surprise me. These are the difficult games for me. Even if I survive the opening then often I have a big time-disadvantage. I experienced this fate several times this season. Besides I also start to get more often problems remembering my analysis. I can accept that I forget some old game-preparation at which I spent only a few minutes but it is more painful when you forget something which you studied in detail at home. Last year such scenario happened already 8 times and at one period it even occurred in 3 consecutive games I played. I discussed the first position already in my article surprises 3. End of 2018 I had spent a lot of hours at analyzing the opening but during the game I couldn't remember anymore one very crucial detail.
[Event "Interclub Opwijk - Deurne"] [Site "?"] [Date "2019"] [Round "?"] [White "Bomans, A"] [Black "Brabo"] [Result "1-0"] [SetUp "1"] [FEN "rnbqk1nr/ppp3b1/4p2p/6p1/3PPp2/1B4B1/PPP2PPP/RN1QK1NR w KQkq - 0 9"] [ECO "A80"] [WhiteElo "2260"] [BlackElo "2301"] [PlyCount "12"] 9. Qh5+ {(There is only 1 game with this position in the megadatabase which was played in 1999 and continued with Bxf4. However Qh5+ was still part of my analysis created in 2018.)} 9... Kf8 10. c3 fxg3 11. fxg3 Qe8 {(In the game I played Nf6 as I forgot my analysis and quickly got a lost position.)} 12. Qe2 Ke7 13. Nf3 Kd8 14. O-O Ne7 {(Here my analysis ended and black is ok.)} 1-0
The next game was played in the club-championship of Deurne against Marcel Van Herck. Marcel normally doesn't prepare his games but for me he likes to make an exception although definitely not more than an hour. Anyway he makes sure that he avoids my preparation although this time he almost didn't manage. I had checked the played sub-line in my preparation but not the sub-sub-line he played. I found it unfortunate as I had even studied that little line extensively a couple of months earlier. However again I couldn't remember it at the board.
[Event "Klubkampioenschap Deurne r4"] [Site "?"] [Date "2019"] [Round "?"] [White "Van Herck, M."] [Black "Brabo"] [Result "1/2-1/2"] [SetUp "1"] [FEN "rnbqk2r/pppp2pp/4pn2/5p2/1bP5/2N2NP1/PP1PPP1P/R1BQKB1R w KQkq - 0 5"] [ECO "A10"] [WhiteElo "2050"] [BlackElo "2301"] [PlyCount "12"] 5. Qb3 {(In the megadatabase there are only 3 games with this position.)} 5... c5 {(8 months ago I had studied this position and my engine had discovered the strong novelty c5. However I couldn't remember it during the game as I didn't expect this line in my game-preparation. I continued with the weaker Bxc3 and only achieved equality after Marcel relaxed a bit.)} 6. Bg2 Nc6 7. d3 O-O 8. a3 Ba5 9. e3 d6 10. O-O h6 {(Black has a very flexible position in which he has decent chances.)} 1/2-1/2
A week later it was again the same bad news due to my failing memory. I am friended with the Belgian FM Marc Lacrosse for already 2 decades so Marc knows he better doesn't allow me to play too many moves of my preparation. In our most recent game played in the Dutch interclubs he chose for that reason to experiment. Of course he was surprised after the game to hear that even that I had analyzed in detail at home but I could only reproduce partly the analysis.
[Event "Interclub Sas van Gent - Landau"] [Site "?"] [Date "2019"] [Round "?"] [White "Lacrosse, M."] [Black "Brabo"] [Result "1/2-1/2"] [SetUp "1"] [FEN "1rbq1rk1/pp4p1/2pbpn1p/3p1p2/2PP1N2/6P1/PPQNPPBP/R4RK1 w - - 0 12"] [ECO "A90"] [WhiteElo "2200"] [BlackElo "2274"] [PlyCount "16"] 12. Nf3 {(Marc wasn't prepared so decided to deviate from our previous game which continued with Ng6. You can't find any game in the megadatabase with Nf3.)} 12... Bxf4 13. gxf4 Kh7 {(In my notes of 2018 I had recommended Kh7 but I hadn't checked it anymore properly during my preparation so I forgot about it during the game. In the game I played the weaker Qe7 and only after an inaccuracy of Marc I managed to equalize. )} 14. e3 (14. Rac1 Rg8 15. e3 g5 16. fxg5 hxg5 17. Ne5 Rg7 ) 14... Rg8 15. Kh1 g5 16. fxg5 hxg5 17. Ne5 Rg7 18. Rac1 Qe7 19. Rg1 Nd7 {(Here my analysis ended and maybe black is still a bit worse but nothing too serious.)} 1/2-1/2
The issue is of course that it is not enough to make analysis. You also need to regularly repeat them otherwise you just forget. Unfortunately I don't see a good solution for it. I've started to use Chess Position Trainer more frequently but I have reached its limitations. If you use CPT then you must make sure there is a balance between complexity and time for training. Also it is important to update your lines regularly so they stay relevant and are checked by the best engines. Below screenshot shows the current status of my white repertoire (about 2600 positions) which I think is about the maximum I can maintain as an amateur.
The opening-lines of the positions discussed above in the article are very rare: of the first one you can't find any games in the megadatabase, of the second one there are only 3 games in the megadatabase and of the 3rd one there exists again no games of it in the megadatabase. It just proofs how thoroughly my analysis are nowadays but simultaneously it became impossible for me to remember everything as am amateur. It would be even anti-productive to insert all those lines into CPT as this would just destroy the basics. Even if know in advance which opening my opponent will play, it is still not easy to study all the analysis of that one opening. I don't have a bad memory which I proofed in part 1 but I will have to accept that I will forget even more often if I continue with making new analysis. Still this is not a good reason for me to stop making them as it is still a lot of fun just discovering beautiful treasurers which you can only do by analyzing.


Tuesday, April 7, 2020

To study openings part 4

I concluded my previous article with the "funny" note that I became a chess-celebrity in Belgium thanks to this blog. There are a number of stronger players in Belgium but it is very hard to become famous by just playing chess. However maybe even greater than this fame is my reputation of being a theoretician which even goes way further back in time than this blog. I can't formulate it better than the already earlier referred report of the KOSK: "Brabo... is feared as chess-player with his good/great/ambitious/exaggerated opening-knowledge". Besides a couple of days ago I suddenly got an email from a Dutch expert asking me to help him with the Graf-line of the Spanish opening so it seems my reputation doesn't stop at the boarders just like the corona-virus.

I hear this song for sure already 2 decades. I always considered it nonsense but I did like it when some of my opponents tried to play the most ridiculous openings just to avoid my "encyclopedic" opening-knowledge (remember e.g. my article scholar's mate). Yes indeed this isn't a good example as I even knew some "theory" about the scholar's mate. Therefore I thought it would be a good idea once to check how much I really know about openings. Who exaggerates or maybe the truth is somewhere more nuanced?

Last week I wrote in a comment that I was busy with a large research and I didn't lie as I spent many hours to investigate the openings of all the standard games I've played in the last 20 years. In total there were 722 of them so it took a while to define from each of them if I had some foreknowledge of the opening. I was lacking time so I had to spread the work over several days  but I believe the final result made the effort worth. However before I start showing the results, I first need to explain to the readers what kind of definition I used for an opening.

There exists no consensus between players about what an opening exactly is. Of course you can consult Wikipedia or Eco but that is not useful for any statistical research. So I used in the end the same arbitrary rule as I did in my article part 2. An unique opening starts from an original position of which maximum 100 master-games (one of both players has a +2300 rating) exist in the megadatabase. So for each of my 722 games I checked at which move the opening started based on an opening-book created from all the master-games existing in the megadatabase. A screenshot explains it always better than 1000 words.

This position occurred on my board in my most recent match in the Belgian interclubs against the Belgian IM Stefan Beukema. Based on the 100 master-games-rule I consider 8.Na4 and 8.Ne4 as 2 different openings. I think everybody agrees both openings should be treated separately.
Next I divided the openings into 3 categories based on my own opening-knowledge:

Category 1: I never played this opening neither did I check it with an engine. I never read about it in a book or forum. Maybe I encountered it in a few online blitz-games but I didn't pay attention to it and just clicked to the next game. Stefan chose 8.Na4 in our game which fulfills all those requirements. I responded with the weak 8....Nfd7.

Category 2: I know something about the opening but it is very limited. I checked maybe some lines during a preparation of a game. Maybe I read something about it in a book or forum. Possibly I played already a standard game with this opening but it was a different line and I didn't check yet the other lines. I have found no games of Stefan in the megadatabase with 8.Ne4 but 8.Ne4 was still part of my preparation. So if he had played 8.Ne4 instead of 8.Na4 then I would've considered the opening as category 2 instead of 1.

Category 3: I've made once an extensive analysis of the different lines with an engine. It can be that the opening popped up in one of my earlier games like I explained in part 2 but it could also be that I once played a correspondence game with the opening. So this doesn't mean necessarily that I am fully up to date of the theory to categorize the opening as 3. Below screenshot is a nice example of such scenario. In the last round of Cappelle La Grande played a month ago, I got 9...d6 on the board. I never encountered it before in any standard game but my opponent had bad luck. I was able to reproduce my analysis made in 2014 till move 18 which I published already on my blog see my game against Roel Goossens in my article fashion. As I introduced a strong novelty at move 15, I think we can consider this a category 3 as opening despite I haven't made any recent updates to the analysis in the last 5 years.

So we have an understanding about how to differentiate between openings and categories. It is time to look at the numbers. I invite people not trusting my data to write me a mail so we can check together and discuss. I do admit that there were a few tricky cases in which you could argue about the interpretation of the category/ opening. Anyway we are dealing here with input from more than 700 games so I think we can safely state that those few boarder cases won't make any serious impact on our statistics. The first table shows per year clearly the number of games played per each of the 3 categories .
The average for the last 20 years was just below category 2: 1,8. The split between the categories is 38% for category 1, 43% for category 2 and only 19% for category 3.

My first year 2001 is clearly the worst which is no surprise as I was rather inexperienced at that time. However I was a bit disappointed to see that my opening-knowledge almost didn't expand in the 2 decades. I've spent an enormous amount of time at analyzing openings. Why is that?

Well the first reason must be that the theory exploded. I already remarked this in 2013 see revolution in the millennium and the speed of it only increased in the last couple of years. Some openings split into 2, 3 or even more openings. Players like to follow fashionable openings so one is always obliged to learn new stuff. However when looking at the figures it is also important to check the mix of the opponents. Therefore I made a new table but this time linked per elo-category. This shows a very different picture of my opening-knowledge.
We notice that the number of lower-rated players have drastically increased over the years while the opposite happened for the higher-rated players. No I didn't get scared but it is the logical consequence of playing only in the neighborhood after the birth in 2007/2009 of my children. That is why I chose for smaller tournaments close to home like the club-championship which has not very strong opposition (see inactivity).

We also notice that my opening-knowledge has little or no influence below 1800 elo. In part 1 I already made the remark that 1800 players know very little theory of openings and this new study just confirmed it.

Next I also find it remarkable that we see a clear increase of opening-knowledge till 2200 but higher it again decreases. No I don't play junk openings against +2200 rated players nor do +2200 rated players ignore theory of the openings. At the higher echelons we see players start to vary their play and try to get their opponents out of book. So it is not like those strong players know less theory at contrary as it is increasingly studied.

Finally the last interesting aspect of above table is that we can definitely see an improvement of my opening-knowledge over the years. I am glad to see my efforts payed off. An increase of 1,7 to 2,3 in the rating-group 2200-2400 seems not much but very few know how much work you need to achieve such gain.

I still have one last question. In which extend did my reputation harm my results? I mean can we see a difference of the average category between games played against people knowing my reputation and games played against strangers. Before we have a look at this, we first need to check about how many games we are exactly talking. Below table shows per year how many of my opponents are aware about my reputation or not. I again agree there are some cases which I wasn't sure about but as there weren't many this will not change the final view.
The difference between the first and the last years is evident. The year 2006 is special as in that year I played the closed master-tournament in Bruges against players knowing me very well. That influenced the average of the year a lot. I grew up in the same province which explains why they were much earlier than others to know my strengths and weaknesses.

In 2012 I created this blog and this must be the reason why suddenly I started to meet much more often opponents being very well aware about my habits. In 40% of my most recent games I experienced that my opponents consulted this blog and didn't hesitate to use my articles against myself. It also explains why I was eager to play again abroad (Netherlands and France) without having this disadvantage.

On the other hand I see my opponents use often very different strategies to cope with the bonus-information available on this blog. Sometimes a cure is worse than the disease as you never know exactly what I have studied. Preparations start to play a big role above +2200 elo so I think it is therefore interesting to focus on the 2 highest categories to see to which effect foreknowledge about myself influences the openings. We know from the previous table that the group of people knowing me well, becomes from 2014 onward substantial so I will only look at the years 2014-2020.
In other words I lose about 0,3 averagely in both categories when opponents know me well compared with strangers. It is not pleasant but I think too many readers would find it a pity that I stop because of it with blogging. Besides by playing more abroad, I can maybe avoid this disadvantage more regularly.

I want to conclude this special article. It is clear that I do know quite a bit about openings. I won't deny that this is much more than the average amateur. However I still encounter too many times openings which are totally new for me so I am still far away from the level of professional players or even Belgian international masters like Steven Geirnaert, Stefan Docx, Bruno Laurent... Now I don't think this article will change much about my reputation as it is almost impossible to get such thoughts extinguished.