b6 in the French Defence?

What are your thoughts on this idea in the advance french? 

The idea is to play ba6 to try trade of the light squared bishop. Several drawbacks I can think of the top of my head are you can't play Qb6 anymore, the knight sorta has to stay on b8 to defend the a6 square. Also as an additional question I've heard that g7-g5 is a possible thematic pawn break in the french, is this pure nonsense?

It's suboptimal and rarely played.

The g5 push depends on circumstances.  It is more commonly seen in the Tarrasch, Universal System (also referred to as the Korchnoi Gambit).  It can be reached via 1.e4 e6 2.d4 d5 3.Nd2 and now:

A) 3...Nf6 4.e5 Nfd7 5.Bd3 c5 6.c3 Nc6 7.Ngf3 (though 7.Ne2 is more popular) Be7 8.O-O

B) 3...c5 4.Ngf3 Nf6 (4...cxd4 and 4...Nc6 are also possible though) 5.e5 Nfd7 6.Bd3 c5 7.c3 Nc6 8.O-O

C) 3...Be7 4.Ngf3 (4.e5 or 4.Bd3 also possible) 4...Nf6 5.e5 Nfd7 6.Bd3 c5 7.c3 Nc6 8.O-O

So now you see why it is referred to as the Universal System.  Can come via 3 different black systems against the Tarrasch, though alternatives are available in all 3 and it cannot be completely forced.

Now 8...g5 threatens 9...g4, deflecting the guard is d4.  White should play 9.dxc5, giving the knight the d4 square.  After 9...g4 10.Nd4 Ndxe5, you have a game.

This idea might exist, but is rare in the advance variation.

I have played this position as Black many times via line B.

Is that why some massa play 3....Qd7 first?

Srs? I play it every single game

thank you massa Pfren

Just because you play something doesn’t make it optimal, and/or common.

White has a big advantage in advanced french

its too slow white should get a dangerous edge with c3 bd3 ne2 0-0, intending f4-f5 soon. The problem is that black has spent so much time swapping away his bad bishop, he doesnt have sufficient pressure on d4 to counterattack vs white's coming kingside attack. (it helps that b6 also excludes qb6 pressure).

To add yet another issue  is that after black commits qd7, if they play ba6, white can just take, and the knight is misplaced on a6, blocking a pawn (taking away the pressure on d4 for quite some time). adding a5 first intending to take back with rook even without qd7 is too slow, white can take on a6, and if rxa6, play normally and play a timely a4 eventually. if black ever swaps on d4, the nc3-nb5 threat is greater than blacks temporary b4 square for his knight.

it is inferior to certain lines of the Owen's in the sense that in those lines with early d5 black has committed knight to f3 slowing down the kingside f-pawn thrust and both nbd2 and qe2 have their disadvantages. In your line, black doesnt have time to start a queenside pawn storm either


its probably still playable and despite being like +1.0 for white, in these "ugly" french positions, evaluation is not as important as conceptual familiarity unless there is some concrete refutation. I just find that white's plans to get a really nagging edge are really easy to execute  and black is like limping to catch its breath for any counterplay.

     ....b6 is just a weaker move in the advance French. It's stronger in some Winawer lines. Here it not only limits black's normal continuations but it doesn't even accomplish its primary purpose of exchanging white-squared bishops.