Stockfish test position (& possible eval bug)

[carldaman]

Hi Carl.

I did not go deep enough into the position, so I do not know if Qh5 is good or bad, but I think that the logic behind such a seemingly strange move might be as follows: when Qh5 and g6 are played, as pawns do not go back, the engine would consider that, when the black king castles short (a very probable option), the king on g8 would be worse covered by the pawn on g6 than a pawn still on g7, as in this case the king will have a pawn less immediately adjacent, and this is an important pawn. Pawns do not go back

The position is still somewhat open, so g6 might be a good move, but might also be a weakness, I did not go deep enough and am undecided.

I have also been frequently 'baffled' by similar engine moves in the past, they sometime prove to have some logic behind, though.

Hi Lyudmil.

I respect your original and independent thinking on chess, but this move is no valid "novelty", so it can't be easily rationalized. Maybe if 1 tempo, and not 2, had been lost, I might concur that inducing a "weakness" might have a point. But here, g6 is a very useful move for Black, leading to a sort of KID setup, and then Black gets in Nf6 for free as well. Deep analysis aided by the underrated and forgotten Deep Fritz 10 engine shows Black can mount a promising and swift pawn storm. DF10 may be one of the few engines that truly plays well in closed positions with flank attacks and pawn storms on the Kingside.

In my database, and backed up by extensive analysis, Nc2 or even O-O are objectively better moves for White, and the masters who played them probably think likewise.

I can post more later when I have more time.

CL

Hi Carl.
I respect your searching after the truth even more, and, after looking more carefully at the position (my first suggestion was just a hypothetical assumption), my opinion is that 10.Qh5 is indeed a bad move (at least imperfect). I would play 0-0 instead (but those are just intuitive assessments, as I do not follow theory at all).

I think that after 9.Bd3 f4 black is actually better, although the position is not as much closed to empower the chain. I would play 9.ef5 instead (Bf5 Bd3), maybe white is better here.

Thanks for taking a closer look with an open mind

Book ended on move 8 actually, and Stockfish chose 9.Bd3 after almost 2 minutes of thinking time. This further suggests it wasn't worried about the ensuing structure. On top of that, I strongly suspect it has an issue with the way it values tempos -- in a recent post of yours, the PV showed SF was dilly-dallying with Nf6-e8-f6 in the face of a strong attack.

Anyway, 10.Qh5 doesn't have to be a losing move to be bad. With correct play for Black, White could come under severe pressure. I've done some more analysis enlisting Houdini Tactical and Komodo CCT in addition to Fritz 10 and other engines. It is quite entertaining, and not necessarily meant to be the best possible play for either side, but just an illustration of the attacking themes and potential pitfalls facing White.

[pgn]

[Event "some analysis"]
[Site "Neo-Sveshnikov"]
[Date "2013.??.??"]
[Round "?"]
[White "Stockfish"]
[Black "Komodo&Houdini&Fritz"]
[Result "0-1"]
[ECO "B32"]
[Annotator "Doe,John"]
[PlyCount "56"]
[EventDate "2012.??.??"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 d6 6. c4 Be7 7. N1c3 a6 8. Na3
f5 9. Bd3 {[%eval 28,27] 110} f4 {[%eval -12,26] 188} 10. Qh5+ $2 {Stockfish}
g6 {[%eval -6,26] 240} 11. Qd1 $8 {[%eval 30,29] forced} (11. Qe2 Nd4) 11...
Nf6 {[%eval -12,25] 166} 12. O-O {[%eval 30,27] 120} Be6 {[%eval -8,25] 249}
13. Nc2 {[%eval 30,27] 115} h5 14. Nd5 g5 15. b3 $5 (15. g3 $6
h4 16. gxf4 gxf4 17. Kh1 Kd7 $5 18. Rg1 $5 (18. Be2 Nxe4) (18. Bd2 Nh5 $17 19.
Be2 (19. Ne1 Ng3+ $3 $17) 19... Ng3+ $1 20. fxg3 hxg3 21. Bh5 Qg8 $40) 18...
Rb8 $5 19. Bd2 Rg8 20. f3 Nh5 21. Rxg8 (21. b4 Ng3+ $1) (21. Ncb4 $2 Ng3+ $3
$19 22. hxg3 hxg3 23. Rg2 Nxb4 24. Bxb4 Rh8+ 25. Kg1 Bxd5 26. exd5 Qb6+) 21...
Qxg8 22. Qg1 Qh7 $1 23. Qb6 Ng3+ $1 24. Kg1 Qg7 $19 25. Nxe7 h3 26. Kf2 Nxe4+
$1 27. fxe4 Qg2+ 28. Ke1 Qh1+ 29. Bf1 Bxc4 30. Qf2 Nxe7 31. Bc3 Qxe4+ 32. Kd2
Qd5+ 33. Ke1 Bxf1 34. Qxf1 Rg8 35. Qxh3+ Kc7 36. Kf2 e4 $1 37. Nd4 e3+ 38. Ke2
Rg2+ 39. Kf1 e2+ 40. Nxe2 f3 $19 41. Nf4 Qc4+ 42. Ke1 f2+) (15. b4 h4 16. h3 g4
$40 17. Kh2 Rg8 $1 $40) (15. f3 g4 16. Qe1 Rg8 17. Kh1 (17. Qh4 Nxd5) 17... g3
18. hxg3 (18. h3 Bxh3 $1 $19) 18... fxg3) 15... g4 16. g3 f3 17. Be3 h4 (17...
Kf7 $5 18. h4 (18. Bb6 Qg8 19. h4 gxh3 20. Qxf3 Qg5 21. Nc7 Rag8 22. Nxe6 Kxe6
23. c5 $5 dxc5 $132) 18... gxh3 19. Ne1 $5 h2+ $5 20. Kxh2 h4 21. Kg1 hxg3 (
21... Qg8 22. Nxf3 Rh5 23. Nxf6 Bxf6 24. Nh2) 22. fxg3 (22. Nxf3 Rg8 $40) 22...
Qg8 23. Qxf3 Qg6 $1 $17) 18. Bb6 Qc8 19. Nc7+ Kf8 $142 $1 $44 (19... Kf7 $5 20.
c5 $5 (20. Nxa8) 20... hxg3 21. fxg3 Nd7 $5 22. Nxe6 Nxb6 23. Rxf3+ $1 gxf3 24.
Qxf3+ Bf6 25. cxb6 Kxe6 $8 26. Bc4+ Ke7 27. Rf1 (27. Ne3 $5 $44) 27... Rh6 28.
Ne3 Nd4 29. Nd5+ Kf8 30. Qe3 Qh3 31. Qd2 Rg6 32. Nxf6 Kg7 33. Qf2 Kh8 34. Nd5
Rag8 35. Qg2 Qh4 36. Rf6 $5 Qh6 37. Rf7 R8g7 38. Rf8+ Rg8 39. Rf2 Rf8 40. Rxf8+
Qxf8 41. Qf2 Qg7 42. Kg2 Re6 $14) 20. Nxa8 (20. Ne3 $5 hxg3 21. fxg3 Rb8 22.
Nxe6+ Qxe6 23. Nf5 Bd8 $5 24. Be3 Ne7 25. Qd2 Nxf5 26. exf5 Qd7 $36) 20... Qxa8
21. Qd2 Qe8 $1 22. Be3 Qh5 23. Bg5 Kg7 $1 24. Be3 (24. Bxh4 Nd7 $19) 24... Bf7
25. Rad1 Bd8 $1 26. a3 Ba5 27. b4 Bxc4 $3 28. Bxc4 Nxe4 $19 0-1

[/pgn]

Some highlights from the analysis:

[d]r2q3r/1p1kb3/p1npb3/3Np3/2P1Pp1p/3B2n1/PP1B1P1P/R2QNR1K w - - 6 20

[d]7r/1p4k1/p1np4/b3p2q/1PB1n1pp/P3BpP1/2NQ1P1P/3R1RK1 w - - 0 29

[Lyudmil Tsvetkov]

Hi Carl.

I did not go deep enough into the position, so I do not know if Qh5 is good or bad, but I think that the logic behind such a seemingly strange move might be as follows: when Qh5 and g6 are played, as pawns do not go back, the engine would consider that, when the black king castles short (a very probable option), the king on g8 would be worse covered by the pawn on g6 than a pawn still on g7, as in this case the king will have a pawn less immediately adjacent, and this is an important pawn. Pawns do not go back

The position is still somewhat open, so g6 might be a good move, but might also be a weakness, I did not go deep enough and am undecided.

I have also been frequently 'baffled' by similar engine moves in the past, they sometime prove to have some logic behind, though.

Hi Lyudmil.

I respect your original and independent thinking on chess, but this move is no valid "novelty", so it can't be easily rationalized. Maybe if 1 tempo, and not 2, had been lost, I might concur that inducing a "weakness" might have a point. But here, g6 is a very useful move for Black, leading to a sort of KID setup, and then Black gets in Nf6 for free as well. Deep analysis aided by the underrated and forgotten Deep Fritz 10 engine shows Black can mount a promising and swift pawn storm. DF10 may be one of the few engines that truly plays well in closed positions with flank attacks and pawn storms on the Kingside.

In my database, and backed up by extensive analysis, Nc2 or even O-O are objectively better moves for White, and the masters who played them probably think likewise.

I can post more later when I have more time.

CL

Hi Carl.
I respect your searching after the truth even more, and, after looking more carefully at the position (my first suggestion was just a hypothetical assumption), my opinion is that 10.Qh5 is indeed a bad move (at least imperfect). I would play 0-0 instead (but those are just intuitive assessments, as I do not follow theory at all).

I think that after 9.Bd3 f4 black is actually better, although the position is not as much closed to empower the chain. I would play 9.ef5 instead (Bf5 Bd3), maybe white is better here.

Thanks for taking a closer look with an open mind

Book ended on move 8 actually, and Stockfish chose 9.Bd3 after almost 2 minutes of thinking time. This further suggests it wasn't worried about the ensuing structure. On top of that, I strongly suspect it has an issue with the way it values tempos -- in a recent post of yours, the PV showed SF was dilly-dallying with Nf6-e8-f6 in the face of a strong attack.

Anyway, 10.Qh5 doesn't have to be a losing move to be bad. With correct play for Black, White could come under severe pressure. I've done some more analysis enlisting Houdini Tactical and Komodo CCT in addition to Fritz 10 and other engines. It is quite entertaining, and not necessarily meant to be the best possible play for either side, but just an illustration of the attacking themes and potential pitfalls facing White.

[pgn]

[Event "some analysis"]
[Site "Neo-Sveshnikov"]
[Date "2013.??.??"]
[Round "?"]
[White "Stockfish"]
[Black "Komodo&Houdini&Fritz"]
[Result "0-1"]
[ECO "B32"]
[Annotator "Doe,John"]
[PlyCount "56"]
[EventDate "2012.??.??"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 d6 6. c4 Be7 7. N1c3 a6 8. Na3
f5 9. Bd3 {[%eval 28,27] 110} f4 {[%eval -12,26] 188} 10. Qh5+ $2 {Stockfish}
g6 {[%eval -6,26] 240} 11. Qd1 $8 {[%eval 30,29] forced} (11. Qe2 Nd4) 11...
Nf6 {[%eval -12,25] 166} 12. O-O {[%eval 30,27] 120} Be6 {[%eval -8,25] 249}
13. Nc2 {[%eval 30,27] 115} h5 14. Nd5 g5 15. b3 $5 (15. g3 $6
h4 16. gxf4 gxf4 17. Kh1 Kd7 $5 18. Rg1 $5 (18. Be2 Nxe4) (18. Bd2 Nh5 $17 19.
Be2 (19. Ne1 Ng3+ $3 $17) 19... Ng3+ $1 20. fxg3 hxg3 21. Bh5 Qg8 $40) 18...
Rb8 $5 19. Bd2 Rg8 20. f3 Nh5 21. Rxg8 (21. b4 Ng3+ $1) (21. Ncb4 $2 Ng3+ $3
$19 22. hxg3 hxg3 23. Rg2 Nxb4 24. Bxb4 Rh8+ 25. Kg1 Bxd5 26. exd5 Qb6+) 21...
Qxg8 22. Qg1 Qh7 $1 23. Qb6 Ng3+ $1 24. Kg1 Qg7 $19 25. Nxe7 h3 26. Kf2 Nxe4+
$1 27. fxe4 Qg2+ 28. Ke1 Qh1+ 29. Bf1 Bxc4 30. Qf2 Nxe7 31. Bc3 Qxe4+ 32. Kd2
Qd5+ 33. Ke1 Bxf1 34. Qxf1 Rg8 35. Qxh3+ Kc7 36. Kf2 e4 $1 37. Nd4 e3+ 38. Ke2
Rg2+ 39. Kf1 e2+ 40. Nxe2 f3 $19 41. Nf4 Qc4+ 42. Ke1 f2+) (15. b4 h4 16. h3 g4
$40 17. Kh2 Rg8 $1 $40) (15. f3 g4 16. Qe1 Rg8 17. Kh1 (17. Qh4 Nxd5) 17... g3
18. hxg3 (18. h3 Bxh3 $1 $19) 18... fxg3) 15... g4 16. g3 f3 17. Be3 h4 (17...
Kf7 $5 18. h4 (18. Bb6 Qg8 19. h4 gxh3 20. Qxf3 Qg5 21. Nc7 Rag8 22. Nxe6 Kxe6
23. c5 $5 dxc5 $132) 18... gxh3 19. Ne1 $5 h2+ $5 20. Kxh2 h4 21. Kg1 hxg3 (
21... Qg8 22. Nxf3 Rh5 23. Nxf6 Bxf6 24. Nh2) 22. fxg3 (22. Nxf3 Rg8 $40) 22...
Qg8 23. Qxf3 Qg6 $1 $17) 18. Bb6 Qc8 19. Nc7+ Kf8 $142 $1 $44 (19... Kf7 $5 20.
c5 $5 (20. Nxa8) 20... hxg3 21. fxg3 Nd7 $5 22. Nxe6 Nxb6 23. Rxf3+ $1 gxf3 24.
Qxf3+ Bf6 25. cxb6 Kxe6 $8 26. Bc4+ Ke7 27. Rf1 (27. Ne3 $5 $44) 27... Rh6 28.
Ne3 Nd4 29. Nd5+ Kf8 30. Qe3 Qh3 31. Qd2 Rg6 32. Nxf6 Kg7 33. Qf2 Kh8 34. Nd5
Rag8 35. Qg2 Qh4 36. Rf6 $5 Qh6 37. Rf7 R8g7 38. Rf8+ Rg8 39. Rf2 Rf8 40. Rxf8+
Qxf8 41. Qf2 Qg7 42. Kg2 Re6 $14) 20. Nxa8 (20. Ne3 $5 hxg3 21. fxg3 Rb8 22.
Nxe6+ Qxe6 23. Nf5 Bd8 $5 24. Be3 Ne7 25. Qd2 Nxf5 26. exf5 Qd7 $36) 20... Qxa8
21. Qd2 Qe8 $1 22. Be3 Qh5 23. Bg5 Kg7 $1 24. Be3 (24. Bxh4 Nd7 $19) 24... Bf7
25. Rad1 Bd8 $1 26. a3 Ba5 27. b4 Bxc4 $3 28. Bxc4 Nxe4 $19 0-1

[/pgn]

Some highlights from the analysis:

[d]r2q3r/1p1kb3/p1npb3/3Np3/2P1Pp1p/3B2n1/PP1B1P1P/R2QNR1K w - - 6 20

[d]7r/1p4k1/p1np4/b3p2q/1PB1n1pp/P3BpP1/2NQ1P1P/3R1RK1 w - - 0 29

Hi Carl.

Very interesting, thanks for the effort!

Poor Stockfish that had to face 3 opponents...

Looking at your 2 analysis highlights, I would be very happy if Mr. Petzke also looks at them, the one thing that springs to mind immediately is that in both positions black wins with its king very badly sheltered, but having formidable storming pawns at the same time. The conclusion can not be but one: it is much preferable, regardless of which way you castle and what pawns you use to storm, to have bad king safety but a mighty pawn storm attack instead. I think this is quite logical actually: when the enemy king is about to die it certainly does not matter how comfortably you feel, whoever attacks first will win the game.

[Lyudmil Tsvetkov]

Thanks, Carl, for the link.

Interesting info.

I think many widely acknowledged theoretical lines are at least a bit dubious, and therefore I prefer instead of learning theory to play something like 1.f3, or 1.e4/d4 f6 with black, in the hope that will swiftly beguile engines to inferior lines. I would even suggest those lines for Graham's book, but I am sure he will decline; although, please notice, that the best game in the 3 Champs so far (and I think this is game 6), the more interesting in content and with the most unusual setup, arose out of a 1.b3 line. So people definitely miss a lot of fun when they do not pay enough attention to 'off' choices.

In any case, I am almost certain that both 1.f3, as well as 1.e4/d4 f6, are objectively much better options than at least half of the lines you will find in most books. And they offer the engines better chances to show their real capabilities at that.

But things are like they are: for the time being I will be the only crazy bloke who on 1.e4 will consistently reply with f6 (not entirely true, because I choose f6 just sometimes; perfectly playable, btw., still almost equal, but some sweet talk will justify an exaggeration)

"Dubious therefore playable" - isn't that a famous quote by Tartakover?
Well, I think the context there was human play, but since engines don't always excel at the opening, forcing them out of book early with offbeat, dubious moves has its merits.

1.b3 isn't all that dubious; it's a big part of my repertoire, in fact

Anyway, you can check out my recent post about the Don Dailey inspired chess 'variant', where each side moves a pawn to the 3rd rank randomly, and then the game begins on move 2.

http://www.talkchess.com/forum/viewtopi ... 94&t=49059

Hi Carl.

Tartakover quotes are ingenious really, but there is nothing like a Fischer quote.
One I remember currently, probably out of context, but still sparky, is My opponents make good moves too. Sometimes I don't take these things into consideration.' It can not get any funnier than that.

My point was that, for example 1.e4 f6 is objectively and theoretically much sounder than at least half of the lines you will find in most engine opening books. Some lines are really a disaster in terms of representing at least rough equality, while 1.e4 f6 is objectively almost equal (as you need at least a couple of moves to lose a position).

I think the major appeal of chess in its current form is that you start from a single position (which inspires holistic conceptions), while at the same time you have the right to choose which way to go. A flaw of FRC is, for example, that this holistic conception is gone. There is something magical about such holistic conceptions.

But, for a searching mind, known theory is bad, you are not an artist when you study theory, you are more of a labourer instead. Therefore, a searching mind would like to experiment, and, with this purpose in mind, almost all moves that are not entirely bad, are perfectly playable, and very often leading to positions a human person has never set her eyes on.

[carldaman]

Very interesting, thanks for the effort!

Poor Stockfish that had to face 3 opponents...

Looking at your 2 analysis highlights, I would be very happy if Mr. Petzke also looks at them, the one thing that springs to mind immediately is that in both positions black wins with its king very badly sheltered, but having formidable storming pawns at the same time. The conclusion can not be but one: it is much preferable, regardless of which way you castle and what pawns you use to storm, to have bad king safety but a mighty pawn storm attack instead. I think this is quite logical actually: when the enemy king is about to die it certainly does not matter how comfortably you feel, whoever attacks first will win the game.

Well, SF only faced Houdini in the original 10.Qh5 game that first revealed the flaw. The rest was my own engine-aided analysis from move 13 onwards.

Very good point about Black's King shelter. I think that two concepts may need to be better codified --
1) asymmetrical king safety, weighting one's king safety separately and differently than the opponent's, which some engines already use
and
2) *distant* king shelter, where the king is not closely sheltered by pawns, but yet it is still hiding behind a pawn chain or pawn storm, at a distance, and cannot be easily attacked

Glad you appreciated my analysis!
Cheers,
CL

[Lyudmil Tsvetkov]

Very interesting, thanks for the effort!

Poor Stockfish that had to face 3 opponents...

Looking at your 2 analysis highlights, I would be very happy if Mr. Petzke also looks at them, the one thing that springs to mind immediately is that in both positions black wins with its king very badly sheltered, but having formidable storming pawns at the same time. The conclusion can not be but one: it is much preferable, regardless of which way you castle and what pawns you use to storm, to have bad king safety but a mighty pawn storm attack instead. I think this is quite logical actually: when the enemy king is about to die it certainly does not matter how comfortably you feel, whoever attacks first will win the game.

Well, SF only faced Houdini in the original 10.Qh5 game that first revealed the flaw. The rest was my own engine-aided analysis from move 13 onwards.

Very good point about Black's King shelter. I think that two concepts may need to be better codified --
1) asymmetrical king safety, weighting one's king safety separately and differently than the opponent's, which some engines already use
and
2) *distant* king shelter, where the king is not closely sheltered by pawns, but yet it is still hiding behind a pawn chain or pawn storm, at a distance, and cannot be easily attacked

Glad you appreciated my analysis!
Cheers,
CL

Yeah, or simply score storming pawns heavier, score minor pieces part of the shelter (that might substitute pawns and therefore justify storming), score squares of the king shelter, defended by heavy pieces (which could also justify storming, even with pawns of the shelter), score chains adequately, etc.

Details otherwise not considered, but really present, could change the assessment of whatever static evaluation and justify dubious-looking storms.

[carldaman]

Programmers should consider creating alternate, analysis-friendly and useful personalities for their engines, even though such personalities may be far from full strength.

For example, I bet someone could come up with an engine that plays pawn storms and flank attacks better than the top engines but might be weaker overall, since it plays other types of positions worse. However, an intelligent end-user won't care about those weaknesses in open games, since they likely already have one of the likes of SFish, Houdini, Komodo, etc., to take care of open positions, and they usually analyze with more than one engine anyway, and, above all, they're able to think for themselves and not blindly trust the engines' choices.

Not many developers have expressed any enthusiasm or willingness to go for such an approach, which puzzles me, since such an engine is badly needed by the chess community. It seems that most programmers are only concerned about chasing rating gains, while the actual quality of analysis, from a human player's perspective, takes a back seat and suffers in the end.

It's a worrisome trend, since many chess players no longer like to think independently of engines, and take everything for granted. If the engine plays a crappy move, it must've had a "deeper" reason. No way the engine could've made a positional mistake, according to them. It's like a form of brainwashing.

A paradigm shift is necessary, where some talented programmer steps up and says: "Darn it, I'm hundreds o' points away from #1 on da rating lists, so I'm not gonna care 'bout'em ratin's! I'll just make sure I develop the most human-like, human-friendly engine, packed with knowledge and regardless of what others think!"

Best regards,
CL

[Kyodai]

"A paradigm shift is necessary, where some talented programmer steps up and says: "Darn it, I'm hundreds o' points away from #1 on da rating lists, so I'm not gonna care 'bout'em ratin's! I'll just make sure I develop the most human-like, human-friendly engine, packed with knowledge and regardless of what others think!"

Those words make me remember Chris Wittington - Thorsten Czub and Chess System Tal...

Nothing new under the Tuscan Sun - or eternal truths never die

[mar]

Wrong: there are engines that support personalities (ProDeo, Glass, ...).
So please stop whining and start tweaking the parameters

[carldaman]

"A paradigm shift is necessary, where some talented programmer steps up and says: "Darn it, I'm hundreds o' points away from #1 on da rating lists, so I'm not gonna care 'bout'em ratin's! I'll just make sure I develop the most human-like, human-friendly engine, packed with knowledge and regardless of what others think!"

Those words make me remember Chris Wittington - Thorsten Czub and Chess System Tal...

Nothing new under the Tuscan Sun - or eternal truths never die

Chess System Tal was/is great , I still have it, it beat Ychess 1.0 in a recent game

[pgn]

[Date "2013.08.28"]
[Round "?"]
[White "CSTAL II"]
[Black "YChess1.0"]
[Result "1-0"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Bxc6 dxc6 5. O-O f6 6. d4 Bg4 7. c3 Bd6 8. Be3
Qe7 9. Nbd2 Nh6 10. Qc2 Nf7 11. h3 Be6 12. Rfd1 O-O 13. dxe5 fxe5 14. Nf1 Qf6
15. N1h2 Qg6 16. Nh4 Qh5 17. Nf5 Bxf5 18. exf5 Nd8 19. Qb3+ Kh8 20. f6 gxf6 21.
c4 Qf5 22. c5 Be7 23. Ng4 a5 24. Nh6 Qc8 25. Rd2 a4 26. Qd1 Qe6 27. Qh5 a3 28.
Nf5 axb2 29. Rxb2 Rg8 30. Rd1 Bxc5 31. Rbd2 Bd4 32. Nxd4 exd4 33. Bxd4 Rg6 34.
f4 Qe7 35. f5 Rg8 36. Bb2 Rxa2 37. Re2 Qc5+ 38. Bd4 Rxe2 39. Bxc5 1-0

[/pgn]

[d]r2n1r1k/1pp3pp/p1pb4/4pP1q/8/1QP1B2P/PP3PPN/R2R2K1 w - - 3 20

Here CSTAL played 20.f6! and won easily

[carldaman]

Wrong: there are engines that support personalities (ProDeo, Glass, ...).
So please stop whining and start tweaking the parameters

Yes, I try to tweak the engine's parameters to experiment with different settings, but it takes a lot of time to get conclusive results, and good settings don't necessarily work well in all the positions of interest.

At least some developers give us settings to tweak. Not all do this

Cheers,
CL