(24-ply)Rybka2.3.2a
(2.20): 13...a6 14.Nxe4 Qd8 15.Nbc3 Nb4 16.Nxd6+ Qxd6 17.d3 f5 18.a3
Nc6 19.Ne2 0-0 20.Bf4
Did Berliner know about 12.Qe2 Be6 13.Qf2?
I e-mailed Hans Berliner about this move, and here is his response
(!!):
John,
Well; that is an interesting move and may very well be best.
My trouble is that I am 77 yrs old and not the analyst I used to be.
I have spent a couple of hours on this and my
current take is that 13.- Nb4; 14. Na3,e:f3; 15. g:f3,O-O-O is best.
Now we have one of those typical situations in
which black is a piece down but White's position is not too enviable. Based on my theories, I would have to vote for
black to at least draw, but it would be more comforting to have a more detailed analysis.
That is the best I can do
at this time.
Hans B.
I have the highest respect for Hans, his achievements and his abilities - as we all should. Hans
has taken the time to respond to the e-mail of an amateur, which he did not have to do. Hans has defended his position in
the past (such as Walter Muir's suggested 12.Qe2) and has taken pride in his analysis.
Berliner published analysis of 12.Qe2 Be6 13.fxe4 Nb4 14.Na3
0-0-0 15.Qf2 in "From the Deathbed" (it was his main line to the fxe4 variation) so he must have considered playing it earlier.
He also suggested in Timman-Arikok, 1988, the improvement 12.Qe2 0-0 13.fxg4 Nb4 *14.Qf2*.
Conclusion
Evidence is presented that supports the claim that 12.Qe2 Be6 13.Qf2!
refutes the Berliner variation of the Two Knight's Defense. The evidence presented is not overwhelming - what do you think?
Note - thanks to A.J. Goldsby for his encouragement in early postings
of this analysis on chessgames.com.
Addendum - an analysis of the position after 12.Qe2 Be6 using
Rybka 2.1, (set to ultra slow and extremely optimistic and set to show the top 3 moves) results in the following:
+1.20/25 13.Qf2 Nb4 14.Bxb5+ c6 15.Nxe4 Qxf2+ 16.Kxf2 cxb5 17.Nxd6+
Kd7 18.Nxb5 Nc2 19.d5 Bf5
+0.90/25 13.Qxb5+ (chessgames member "monad" has looked at this
line and shown that Black can cause white a number of problems)
+0.87/24 13.Nc3 (I have posted some analysis of this line on chessgames.com
but think that it has been superceded by 13.Qf2)
Analysis of 12.Qe2 Be6 13.Qf2: After 142 hours (screenshot
available to prove this)
1.25/28 13...Nb4 14.Bxb5+ c6 15.Nxe4 Qxf2 16.Kxf2 cxb5 17.Nxd6+
Kd7 18.Nxb5 Nc2 19.d5 Bf5 20.N1a3
1.25/28 13...exf3 14.Bxb5+ Kd8 15.gxf3 Rb8 16.Be2 Nb4 17.Na3 Bxg3
18.Qxg3 Qxd4 19.Qg5+ Kc8 20.Qe3
1.73/28 13...Bxg3 14.Bxb5+ c6 15.Bxc6+ Ke7 16.Qxg3 Qxg3+ 17.hxg3
Rac8 18.fxe4 Nb4 19.Na3 Rxc6 20.d5
Here is analysis of the 12.Qe2 O-O line:
12. Qe2 O-O
13. fxg4 Bxg3+
14. Kd1
and now the top 9 possibilities:
A 14... Nf6
15. Nc3 (15.
Kc2 Nxg4 16. Nc3 f5 17. Qxb5 +1.36/21) (15. g5 Ng4 16. Kc2 b4 17. a3 +1.20/21)
15... Rfe8 (15... Nxg4 16. Kc2 (16. Nxe4 Rae8 (16... Nf2+ 17. Nxf2
Bxf2 18. Qf3 Rab8 19. d5 Bc5 20. Bd3 g6 21. Kc2 a6 22. g4 Bd4 +2.07/19) 17. Kc2 Nxh2 18. d3 h6 19. Qd1 f5 20. Nxg3 Qxg3
21. Bd2 Qd6 22. Rc1 Nxf1 +1.32/20) 16... c6 (16... f5 17. Qxb5 Rab8 18. Qd5+ Kh8 19. b3 Rbd8 20. Qa5 Nf2 21. hxg3 Qxh1 22.
Ba3 Rf7 +1.96/21) 17. a4 f5 18. axb5 cxb5 19. Nxb5 Qh6 20. Ra3 Nf2 21. Rxg3 Nxh1 22. Rh3 Qf4 +1.93/20)
16. Kc2 (16. g5 Ng4 (16... Nh5 17. Qxb5 Bxh2 18. Ne2 Rab8 19. Qd7
Ng3 20. Nxg3 Qxg3 21. Bc4 Rf8 22. Qh3 Qxh3 +2.64/23) 17. Kc2 Rad8
18. Nxe4 Nf2 19. hxg3 Qxh1 20. Nxf2 Rxe2 21. Nxh1 Re1 22. Bxb5 Rxh1
+2.61/25)
16... b4 (16... c6 17. d3) (16... Nxg4 17. Nxe4 +1.45/21)
17. g5 +1.44/21
B 14... b4 15. d3 (15. a3 b3 16. g5 c6 17. Nc3 +0.91/22) 15... Nf6
16. dxe4 Nxg4 17. Kc2 +1.64/20
C 14... Rae8 15. Nc3 (15. Qxb5 Nf6 16. Kc2 Nxg4 17. b3 +1.52/20)
15... c6 (15... Nf6 16. g5 Ng4 17. Kc2 +1.77/21) (15... Nxc3+ 16.
dxc3 b4 17. Qe3 +2.08/21) 16. Nxd5 cxd5 17. Qxb5 +1.75/24
D 14... Rfe8 15. Nc3 (15. Qxb5 c6 16. Qxc6 Nf6 17. Bc4 +1.41/22)
15... c6 16. Nxd5 cxd5 17. Qxb5 +1.64/23
E 14... a6 15. Nc3 (15. a4 b4 16. d3 Nf6 17. dxe4 +1.47/20) 15...
Nf6 16. Nxe4 Rae8 17. Nxf6+ +1.94/24
F 14... Rad8 15. Nc3 (15. Qxb5 Bf2 16. Nc3 Qxg4+ 17. Qe2 +1.31/23)
15... Rfe8 16. Qxb5 Nf6 17. Kc2 +1.64/21
G 14... Rab8 15. Nc3 (15. d3 Nf6 16. Nc3 exd3 17. Qxd3 +1.61/21)
15... Nf6 16. Nxe4 Rfe8 17. d3 +1.95/23
H 14... Kh8 15. Nc3 (15. Qxb5 Nf6 16. Nc3 Nxg4 17. Nxe4 +1.65/21)
15... Nf6 16. Nxe4 Rae8 17. d3 +2.03/23
I 14... c6 15. Nc3 (15. d3 exd3 16. Qf3 Bf2 17. Nc3 +1.26/22) 15...
Bf2 16. g3 Bxg3 17. Bg2 +1.41/20
July 26, 2007 Rybka2.3.1 analysis: after 14.Kd1:
(29-ply)
1. +- (1.55): 14...Rfe8 15.Nc3 c6 16.a4 b4 17.Nxe4
2. +- (1.55): 14...c6 15.Nc3 Rfe8 16.a4 b4 17.Nxe4 f5 18.Qf3 fxe4 19.Qxg3
3. +- (1.73): 14...Rae8 15.Nc3 c6 16.Nxd5 cxd5 17.Qxb5 Bf2 18.Be2
4. +- (1.87): 14...Nf6 15.g5 Ng4 16.Kc2 b4 17.a3 Nf2 18.hxg3 Qxg3 19.axb4
5. +- (1.93): 14...Rad8 15.Nc3 Rfe8 16.Qxb5 Nf6 17.Kc2 Nxg4
6. +- (1.97): 14...b4 15.d3 Nf6 16.dxe4 Nxg4 17.Kc2 Nxh2 18.Nd2 Rad8 19.Qd3 c5 20.d5 Rfe8 21.Kb1
7. +- (2.16): 14...Bf2 15.g3 Qf6 16.Qxe4 c6 17.Bd3 g6 18.Nc3 Nb4 19.Ne2 Rad8 20.Qf4 Bxd4 21.Qxf6
8. +- (2.18): 14...h6 15.Nc3 c6 16.a4 b4 17.Nxe4 Rae8 18.d3 Bc7 19.h3 Bb6 20.Qf2 Qd8 21.Bd2