perfidious: < vinidivici: When the game as early as this, its hard to say its good or bad except the move is so bad or an error....>
This generalisation is far too broad to be of use.
<....We just look for the better position or strategy. 11...g6, in my eyes, its not bad move.
Yes, i do notice the threat Bxh7+....>
There is already a need for concrete analysis by Black in view of his opponent's threat of direct attack on the king. Simply looking at abstract considerations is not enough.
<....But, i prefer 11...f5 or (11...f6 to loosen the king beachhead a bit).
And 11...h6 looks decent.>
Black doubtless gave thought to most, or all, of these possibilities.
From the start: 11....f5 is a move which appears to give White too free a hand-he has a juicy target at e5, plus the backward pawn to play against in the open file. This should be very promising.
Your suggestion 11....f6 may well be best, to play for ....e5 with White's king in the centre and no safe haven. In this case, Bacrot may well have come to regret his early aggro with h4.
The move 11....h5 has the drawback of encouraging White to play for the standard setup of Bc2 and Qd3, when a further kingside weakness will be forced.
<....But its hard to say exactly whats the best move, in the opening.>
Not always true, and certainly not in sharper openings where a single tempo can mean the difference between triumph and disaster.