If you are a reader of this blog, you know I love giving names to the bishop and knight pairs because it gives Chess960 more ways to distinguish between start positions. I think of the titular bishops as "bishops without a diocese" and even great players like Yasser Seirawan have been perplexed about how to deploy them (commentary from the Kings and Queens 960 tournament 2011).
So here is a discovery I have made about them which is relevant to a few dozen starting positions (SPs) in Chess960.
SP505: Pawn structure with titular bishops separating the king and queen
In this example, I've played out the position to show the basic strategy available to both players:
- In SP505, the king is unlikely to castle queenside because four pieces have to be cleared out of the way.
- The queenside is very heavy in pieces. The rook and queen team combine to allow a rapid space gain on the queenside by pushing pawns there (even the rook pawn).
- The titular bishops are deployed to the queenside in the space made available, so that they form a powerful diagonal battery attack against the enemies king.
- Now the queen switches between backing up either colour of bishop using the freed squares on the back rank, so that diagonal battery is at maximum strength.
- The twist in the strategy is that white does not castle kingside and so does not give black this same strategic option.
- The e-pawn is played to e3 so that it does not get in the way of the diagonal battery and the king plays to e2. This is safe, because white has gained so much queenside space that black cannot organise any kind of diagonal attack or knight attack against the king on e2.
- Now white uses the kingside pawns as a storm front to break open blacks kingside defences to combine a crushing attack in combination with the bishop battery. The queenside rook is shifted across the back rank to aid in the kingside storm attack.
Do you see this strategy? It works for black as well if white is not vigilant. The point is that when the king and queen are separated by the titular bishops in the middle, this strategy almost plays itself. In fact, I studied this SP in the LSS database only to find the rough sketch of this idea repeated a number of times.
Now I hear some critics of Chess960 say that this means that SP505 is relatively crude, because the strategy is so clear and potentially crushing. However, I looked at this SP in detail with Houdini-4, and I found that in fact, black has some amazing and efficient ways of undermining whites ideas. For example, check out the trial game of SP393 that Mark Weeks and I played with the titular bishops where black snuffed out this plan right out of the door!
So to me, the titular bishops in the combination [QBBK] or its mirror, are a wonderful study in how black efficiently prevents the strategy outlined here or deploys it themselves if white is clueless to it.
Who says that there is no theory or nothing to remember in Chess960 :-)