Chapter 3 Kaku-Kawari (Bishop Exchange Opening)
Section 2 Bo-Gin
SECTION 2 Kaku-kawari Bo-Gin
History of trial-and-error
The kaku-kawari bo-gin may seem simple at a glance, but is profound in its own right. You may ask, what's so profound about the bo-gin? Let me begin with the basic idea and the successful position it leads to. Look at Diagram 1. Take note that White's Silver is on 6c and a Pawn on 1d.
White in hand: B 9 8 7 6 5 4 3 2 1 +---------------------------+ |wL wN * wG wK * * wN wL |a | * wR * * * * wG * * |b |wP * wP wS wP wP wS wP * |c | * * * wP * * wP * wP |d | * wP * * * * * bP * |e | * * bP * * * * bS bP |f |bP bP bS bP bP bP bP * * |g | * * bG * * * * bR * |h |bL bN * * bK bG * bN bL |i +---------------------------+ Black in hand: B Diagram 1 Up to S-6c
Moves from Diagram 1
1.P-1e Px1e 2.Sx1e Lx1e
3.Lx1e P*1c 4.P*1b S-2b
5.B*6f (Diagram 2)
The third move cited above, Sx1e, is a well-known tesuji. The rest of the moves are no less famous.
White in hand: B S 9 8 7 6 5 4 3 2 1 +---------------------------+ |wL wN * wG wK * * wN * |a | * wR * * * * wG wS bP |b |wP * wP wS wP wP * wP wP |c | * * * wP * * wP * * |d | * wP * * * * * bP bL |e | * * bP bB * * * * * |f |bP bP bS bP bP bP bP * * |g | * * bG * * * * bR * |h |bL bN * * bK bG * bN * |i +---------------------------+ Black in hand: L Diagram 2. Up to 5. B*6f
At Diagram 2, the position is in favor of Black. He has two effective moves to play: P1a+ and L*8d.
But you cannot be too optimistic about it. Bo-gin may be effective against the reclining Silver, which White in Diagram 1 is likely to play. But against the haya-guri-gin, it is said to be not effective. Next I will explain how these tactics fare against each other.
Let me remind you that the reclining Silver side usually plays P-4d, and P-4e, thereby restraining the haya-guri-gin player's moves. So, we cannot tell at all which one is the best of the three tactics: bo-gin(climbing Silver), haya-guri-gin(rushing Silver), and koshikake-gin(reclining Silver). Doesn't this strike you as intriguing?
Now we will look into the history to see how the haya-guri-gin had its day against the bo-gin.
Moves from the very beginning:
White in hand: nothing 9 8 7 6 5 4 3 2 1 +---------------------------+ |wL wN * wG wK * * wN wL |a | * wR * * * * wG * * |b |wP * wS wP wP * wS wP wP |c | * * wP * wB wP wP * * |d | * wP * * * * * bP bS |e | * * bP * * * * * * |f |bP bP bS bP bP bP bP * bP |g | * * bG * * * bB bR * |h |bL bN * * bK bG * bN bL |i +---------------------------+ Black in hand: nothing Diagram 3 Up to 12. P-4d.The B*5d as a countermeasure to Black's bo-gin was first played by Masao Tsukada. Kozo Masuda's answer to that as a Black player was B*3h. It was back in 1950's that these moves were played. Yasuharu Oyama played many kaku-kawari games in which he mainly played White. The players wracked their brains how to realize a favorable position after (w)P-4d. Thus, the position in question(Diagram 3) was a pet problem for them, from which they refined the tactics move by move through trial and error. Now, there are two effective moves to play by Black: P-2d and K-6h. Let me show you two actual game records where Black successfully steered the game in his favor.
First, from the Aono-Nakahara game played in 1989 as the Oh-za-sen, No1. They had exactly the same position as shown in Diagram 3.
Moves from Diagram 3:
1.P-2d Px2d 2.Sx2d Sx2d
3.Rx2d G-3c (Diagram 4)
White in hand: S P 9 8 7 6 5 4 3 2 1 +---------------------------+ |wL wN * wG wK * * wN wL |a | * wR * * * * * * * |b |wP * wS wP wP * wG * wP |c | * * wP * wB wP wP bR * |d | * wP * * * * * * * |e | * * bP * * * * * * |f |bP bP bS bP bP bP bP * bP |g | * * bG * * * bB * * |h |bL bN * * bK bG * bN bL |i +---------------------------+ Black in hand: S P Diagram 4. Up to 3. G-3c.The last move, (w)G-3c, was a natural good move, preventing the Black's Rook from penetrating into White's camp. If Black plays R-2h here, the following will await him: P*2g, Rx2g, Bx2g, Bx2g, R-2b. Not very promising for Black.
Moves from diagram 4:
1.R-2e S*2d 2.R-2h R-2b
3.S-6f P*2g 4.Rx2g Bx2g+
5.Bx2g S-3e 6.P*2h (Diagram 5)
White in hand: R 9 8 7 6 5 4 3 2 1 +---------------------------+ |wL wN * wG wK * * wN wL |a | * * * * * * * wR * |b |wP * wS wP wP * wG * wP |c | * * wP * * wP wP * * |d | * wP * * * * wS * * |e | * * bP bS * * * * * |f |bP bP * bP bP bP bP bB bP |g | * * bG * * * * bP * |h |bL bN * * bK bG * bN bL |i +---------------------------+ Black in hand: B S P Diagram 5. Up to 6. P*2h.Aono played R-2e, temporarily, to induce White's S*2d, then took the Rook back on 2h. Playing S-6f, bringing pressure on Bishop's head, Black exchanged R for B. At Diagram 5, Black enjoys a better position, with Bishop and Silver in hand.
Moves from diagram 5:
P-4e 7.S-5e K-4b
8.G-3h P-7e 9.Bx4e G-5b
10.P-3f S-4d 11.Sx4d Gx4d
12.B*8h (Diagram 6)
White in hand: R S 9 8 7 6 5 4 3 2 1 +---------------------------+ |wL wN * * * * * wN wL |a | * * * * wG wK * wR * |b |wP * wS wP wP * * * wP |c | * * * * * wG wP * * |d | * wP wP * * bB * * * |e | * * bP * * * bP * * |f |bP bP * bP bP bP * * bP |g | * bB bG * * * bG bP * |h |bL bN * * bK * * bN bL |i +---------------------------+ Black in hand: S2 P2 Diagram 6. Up to 12. B*8h.Black's S-5e through B*8h was a series of smart moves.
After Diagram 6:
S*5e 13.B-5f S7c-6d 14.B-8c+ N-7c
15.P-5f
Black continued playing skillfully, ending up taking White's S on 5e, which secured Black's victory.
Back at (b)S-6f, what would have happened if White had played S-2e? Actually, we have another game record with that very move in it.