I was wondering if the counter c5?! would actually work for black to play in response to white’s defense against a queen’s pawn game. Here are the moves that could be done…
1 d4 c5
2 d4xc5 Qa5†
3 Bd2 Qxc5 (does the bishop want to come out to play?)
Result: black regains lost pawn and ends up with the better development. Also, queen is in fully maneuverable position along the board but she ain’t going to be the only attacker if black knows what he’s doing.
Alternatively, the queen could protect the queen in this variation of the Sicilian defense (if still a bit unorthodox), 3 … Qxc5 and black is up a pawn and controls the board (white’s bishop is also blocked).
Another thing that could happen is that white does not take but proceeds to set up a stonewall attack. Maybe he also sees the check ahead. Well…c5xd4 on the next move and white loses his stonewall right off the bat.
I also calculated this possible formula after 2 … Qa5†.
3 Nc3 Qxc5
4 Bf4 (attacking knight) Nc6
Now who appears to have a better control of the board right now? Black or white? (And kiss that stonewall goodbye!)