bob000 wrote on 08/15/06 at 03:14:16:
I don't think either of these lines are playable. 7...f6 xd4 8.xg5 xe5 and now moving the knight leads to an ending a pawn down and protecting it isn't too hot either. 7..b5 drops a piece to 8.Bxd5 Qxd5 9.xd4.
Continuing, after 9. cxd4 we have 9....Qxg2 10. Rf1 and Black has plenty of compensation for the knight.
Namely, a couple of pawns, better pawn structure, a safer king, and the initiative.
Dan Heisman has produced a monograph (which I have not read) claiming that 6....Nxd4 is better than Bb4+
Play might continue
10...............Bb4+
11. Nc3 f6
12. Qc3 Qxc3
13. Nxc3 Bg4
14. Nd2 exd4
15. Nxb5 0-0-0
16. f3 Rhe8 and this rook should manage to get to the 7th.
Although Rybka rates this position =/+, it is possible that White's extra piece could prevail before the endgame.
For the above reasons, it prefers 9. f3 to an immediate cxd4.
But 7......f6 looks less strong.