Znosko-Borovsky, in The Middle Game in Chess, p. 105, claims that in the above position White has the
advantage in space.
"with two centre-pawns in the fourth rank and two well-developed knights. Black's forces occupy the first three ranks,
with little hope of enlarging their scope."
Znosko-Borovsky claims that 11.Nb3 is best for white.
"The explanation is that, with an advantage in space, it is less important to threaten the enemy than to prevent him
from extricating himself from his cramped position and to deny him the possibility of making any threats himself."
Znosko-Borovsky analyzes the sequence 11.Nb3 f6 12.f5 b6 13.Bf4 Bb7* 14.Bxd6 cxd6 15.Nd4 etc. and shows
how white can gradually build positional pressure.
However, a computer program evaluates the diagrammed position as follows:
Analysis by Rybka 4: (28-ply)
[-0.28] 11.Kf2 f6 12.Nf3 b5 13.Re1 Ng6 14.g3 Bb7 15.b3 Rad8
Analysis by Rybka 3: (25-ply)
1. [-0.37] 11.Kf2 f6 12.Nf3 Ng6 13.g3 b5 14.Re1 Bb7 15.a3 Rad8 16.Bd2 c5 17.Rad1 Rd7 18.Nd5 Ne7 19.Nc3 Nc6
2. [-0.42] 11.Rd1 Ng6 12.f5 Ne5 13.Bf4 f6 14.h3 g6 15.fxg6 hxg6 16.Rf1 Be6 17.Nf3 Bc5+ 18.Kh2 Bc4 19.Rfe1 Nxf3+
20.gxf3 Bf2 21.Red1 Re7
3. [-0.43] 11.Nf3 Bc5+ 12.Kh1 f6 13.Bd2 b5 14.Rfe1 Bb7 15.a4 Rad8 16.e5 fxe5 17.fxe5 Bb6 18.Bg5 h6 19.Bxe7 Rxe7
20.h3 b4 21.Ne4 Bc8 22.a5 Ba7
4. [-0.45] 11.Nb3 b6 12.Bd2 f6 13.Rfe1 Bb7 14.Rad1 Rad8 15.Bc1 Ng6 16.g3 Bb4 17.Rxd8 Rxd8 18.Bd2 a5
5. [-0.46] 11.e5 Bb4 12.Ne4 Ba5 13.c4 Nf5 14.Nf3 Nd6 15.Ned2 Bb6+ 16.Kh1 Nf5 17.Ne4 Ne7 18.Re1 Bf5 19.b4 h6 20.c5
Ba7 21.a3 Nd5 22.Ng3
The numbers indicate that the machine thinks that the position is more promising for black. How can this this
be?
It seems that Znosko-Borovsky's elements of chess (position, time, space, force) only indicate whether or
not a position is 'promising' - you would have to perform a deep and thorough search through the promising variations (including
a minimal amount of search through the initially unpromising but 'interesting' lines such as sacrifices) to better estimate winning
chances. White cannot use the pressure from his pieces to sustain the space advantage of the position, and the adaptive
capacity of the black pieces can take advantage of this.
*13...Bxf4 14.Rxf4 c5 15.Rd1 Bb7 16.Rd7** Rac8 17.Rf3 Bc6 18.Rd1 Kf7 with possibly a very small advantage
to black.
**16.Rf2!? Nc6! -0.70/21 17.Re2 a5 18.Rd7 Rac8 19.Rd1 Ne5 20.Nd2 Rcd8
