Why do players play this move (bishop to b6) in bullet chess?

Question

I've often seen (on lichess, I play only bullet, at ratings 1800ish) black play the f8 bishop to c5, and then if white challenges it by playing their c1 bishop to e3, black retreats their bishop from c5 to b6, and then if white captures, black recaptures with the a7 pawn.

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1. Bc5  Be3 2. Bb6 Bxb6 3. axb6

Why is this a good move? I've see it CONSTANTLY in a variety of openings, and I myself never play this way.

It seems a bad move for black to me because

a) you lose a tempo.

b) you double your pawns.

c) yes, you do get an open file for your rook, but ... so what, quite frankly? It's a bullet game. You are probably not going to have the time to think of some ingenious rook lift in the middle of the game. It just seems too risky to utilize that a-flank with the rook in a bullet game, at least for the players at my level. Indeed, I can confirm that I can't recall a single game where black utilized the strategy above and actually got something worthwhile out of it. The rook never made an impact on the a-file in a single bullet game that I've played where black played above strategy.

So why do players do this?

Answer 1

Actually, ..Bb6 is a sound move not just in Blitz. The Italian and Scotch game are filled with it. There are plenty of reasons why you would make it:

• After 1.e4 e5 2.Nf3 Nc6 3.d4 exd4 4.Nxd4 Bc5 5.Be3 White is threatening to win a piece, so Black can retreat to b6 and prevent his bishop from hanging.
• Let's assume a central formation like e4+d3 vs e5+d6, with a Black bishop on c5 and a White bishop on e3. It is good for Black to retreat to b6 (even if ...Bxe3 or even just leaving it on c5 could sometimes be considered) in order to trade them on that square and open the "a" file. In your post you give a lot of importance to the fact that this doubles pawns and very little to the opening of the file. But I would say that, specially in Blitz, the file is way more important! White will have to worry about the a8 rook for the entire game.
• Finally, Black could have retreated to b6 (or a7) to prevent a trade and keep a powerful bishop on the a7-g1 diagonal.

Answer 2

It's a trap.

You really try to reason too much about strategic aspects. This is a move that may not be considered sound in real chess... but we are talking about bullet here. And not Magnus Carlsen level bullet, which often almost looks like real chess, but Patzer level that more often than not is just bloody chaos.

Premoving is very common in bullet and there are tons of cheesy traps that try to exploit that.

This looks like one of them. Black hopes that White premoves Be3xc5, which (after Bc5-b6) will actually play out as Be3-c5 without capture, followed by ...Bb6xc5.

Answer 3

Keeping the Bishop on that diagonal is very aggressive which is good in fast time controls.

Trading the bishop often gives the other side more control of the center and an open f-file.

By moving to b6 white will waste two moves and accomplish nothing where black now has a rook on an open file (which is a gain of time). Furthermore, the rook is a more powerful piece than the bishop and the pawn on b6 can support c5.

Doubled pawns aren't inherently weak. They typically increase mobility. They're only weak if the other side can exploit the weakness.

Answer 4

After ...axb6 the a file is open, a Pawn goes nearer to the center, and these might be assets for Black. Black's Pawn structure now is not inferior in my view. Furthermore, if a Pawn was on d6, defending Black's Bishop, White probably threatened Bxc5, worsening Black's Pawn structure after ...dxc5. And if Black instead took on e3, White could play fxe3, increasing control of the center and opening the important f file.