Two Criminals, Part Two

Last week we analyzed the games where great world champions (Fischer, Petrosian, Smyslov) happily parted with their fianchettoed bishops to isolate and double their opponent's pawns, turning them into long-term weaknesses. Another famous world champion, Mikhail Tal, went even further. He traded his Bg7 just to accomplish the b7-b5 advance to start an expansion on the queenside. As you can see in the following games, he had mixed results there:

In the first part of this article I mentioned that as much as I was suspicious at first, at the end I embraced Fischer's idea. Not so with Tal's concept. It is difficult for me to give up such a powerful bishop just to advance my queenside pawns, and therefore, I can only imitate the signature McKayla Maroney expression: not impressed. It is the games like the next one that show the big real danger of such a trade:

Another Bxc3 trade was pioneered by the great Tigran Petrosian. It is very close by its spirit to the Nimzo-Indian Defense where Black tries to blockade the position (we discussed this concept here). 

The final position where the opponents agreed to a draw is probably slightly better for Black.

You shouldn't think that when Black plays Bxc3 just to blockade the position he is playing for a draw. Just look at the next positional/tactical masterpiece by Mikhail Tal (thanks to our reader kamalakanta for mentioning this game in his comment to the first part of the article!).

If White tries to break the blockade it will cost him some material and it can easily backfire as the next game of another world champion shows:

At the risk of being called Captain Obvious, let me sum up: giving up the fianchettoed bishop just to advance the queenside pawns looks very risky. Meanwhile, the positional Bxc3 trade to blockade the position is quite safe.