In Queen's Pawn openings the move B-g5 is always good as Black cannot very well castle on the Queen's side on account of the open c-file in which White would soon obtain an overwhelming attack. Another good square for the Queen's Bishop is in Queen's Pawn openings b2 from where the Bishop supports the advance of the King's Knight to e5. In this case the Queen's Knight should be developed to d2 instead of c3 so as not to obstruct the line of the Bishop. The same holds good for the development of Black's Queen's Bishop.
In King's Pawn openings it is dangerous for the Queen's Bishop to leave the long diagonal in which he is originally posted as the opponent might threaten to gain a foothold in the f-line with a Knight, provoking a weakening move with the g-Pawn. The position of Diagram 54, which occurred in a game between Teichmann and Rubinstein in the Karlsbad Tournament, 1911, furnishes an instructive example. White played (1) P-a4, trying to make use of the advanced position of Black's b-Pawn for opening the a-file for his Rook, and Black replied B-b7. This crosses White's plan, as after (2) Pxb5, Pxb5; it would not be White but Black who would gain control of the a-line.
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8 | #R | | #B | #Q | | #R | #K | |
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7 | | | | | #B | #P | #P | #P |
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6 | #P | | #Kt| #P | | #Kt| | |
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5 | | #P | #P | | #P | | | |
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4 | | | | | ^P | | | |
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3 | | | ^P | ^P | | ^Kt| | |
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2 | ^P | ^P | ^B | ^Kt| | ^P | ^P | ^P |
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1 | ^R | | ^B | ^Q | ^R | | ^K | |
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DIAGRAM 54.
However, Black should not have withdrawn the Bishop from the King's wing, for White can now play his Queen's Knight via f1 and g3 or e3 to f5 unless Black weakens his Pawn position by P-g6. The proper way to answer White's first move would have been either B-e6 or P-b4. The latter is a Pawn move, but in the present case it cannot be considered a loss of time as White, too, has made a Pawn move which does not further his development.
The game went on as follows: (2) Kt-f1, Q-c7; (3) Kt-g3, P-g6; White's aim is accomplished. He has provoked a weakness which furnishes a mark for his attack. The way to conduct the attack— after completing the development by B-g5, will be to open the f- file for the Rook by advancing the f-Pawn. This advance can be prepared by P-h3 and Kt-h2. Of course, White would prefer to do without the move of the h-Pawn; but h2 is the only favorable square for the Knight f3, as neither from d2 nor from h4 he has an opportunity to help the attack while from h2 he may go to g4, bearing on both of the weak squares f6 and h6.
Black has little chance for counterattack. The only thing he can do is occupy the Queen's file with his Rooks and opening it by P- d5 and Pxe4. His Queen's Bishop, however, is badly placed in any case as he has no open diagonal to work in, and he will have to get back into play via his original square c8.
White's King's Bishop is not well placed either and is practically condemned to play the role of a Pawn by protecting the square d3 without, at the same time, attacking anything. There is, of course, a chance for him to be useful in the diagonal a2-g8. It may be said that in King's Pawn openings White's King's Bishop comparatively seldom has an opportunity to take an active part in the battle. He is mostly exchanged at an early stage of the game for Black's Queen's Knight or Queen's Bishop. In Queen's Pawn openings, however, he finds a great field of action in the unobstructed diagonal b1-h7. In this diagonal he can also be used in all openings starting with P-e4 in which Black does not advance his King's pawn to e5, as White can open the diagonal at any time by playing P-e5.
Generally speaking, Bishops should not be placed in diagonals which are obstructed by Pawns of their own army, and Pawns moves should be avoided which close a diagonal formerly open to a kindred Bishop. A striking illustration of the importance of this rule will be found in the play which developed in the position of Diagram 55 in a game between Teichmann and Dus Chotimirski in the Prague Tournament 1908. Black, on the move, played (1)…, Kt-e5, disturbing the symmetry of the position to his advantage by opening the diagonal of his Queen's Bishop without allowing White to make a similar maneuver. After (2) Ktxe5, Bxe5; (3) Q-e2, o-o; (4) Ra1-d1, Q-e7; White yielded the temptation to drive away the disagreeable Bishop e5 by (5) P-f4, a move which had to be followed up with the advance of the e-Pawn who otherwise would have remained very weak, not being protected by another Pawn.
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8 | #R | | | #Q | #K | | | #R |
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7 | | #B | | | | #P | #P | #P |
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6 | #P | | #Kt| #B | #P | #Kt| | |
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5 | | #P | | | | | | |
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4 | | ^P | | | | | | |
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3 | ^P | | ^Kt| ^B | ^P | ^Kt| | |
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2 | | ^B | | | | ^P | ^P | ^P |
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1 | ^R | | | ^Q | | ^R | ^K | |
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