Yet another trap in the King's Gambit

I have previously shown (here and here) that in the King's Gambit Accepted after 3.Nf3, 3...f6? 4.Bc4 g5? 5.Nxg5! is crushing. My opponent in the following game found a slightly different ...g5 and ...f6 "defense," with equally grisly results. Incidentally, Houdini 3 points out 5...h5! (stopping Qh5+) 6.Nh3 d5! as preferable to accepting the knight, although White still gets a huge advantage.

The play in the game continuation is reminiscent of the main line of Damiano's Defense, which goes 1.e4 e5 2.Nf3 f6? 3.Nxe5! fxe5 4.Qh5+ Ke7 5.Qxe5+ Kf7 6.Bc4+ d5 (best) 7.Bxd5+ Kg6 8.h4! In both lines White's queen, king bishop, and h-pawn kick Black's poor king all over the board.

My play was slightly inaccurate. White mates two moves faster with 11.h5+! Kh6 12.Qxf4+ Qg5 (12...Kg7 13.h6+! and mate next) 13.Qxf8+ Qg7 and now White can choose between the classical 14.d3# (Allgaier-NN, 1807) and the modern preference 14.d4# (Green-Kempfe, Minnesota 1982). By the same token, 15.h6+! would have forced mate a move faster than my 15.Qf7+.

One would be tempted to say, "Never play ...f6 when defending against the King's Gambit!", but that would be too dogmatic. As Bobby Fischer observed in his famous article A Bust to the King's Gambit, after 1.e4 e5 2.f4 exf4 3.Nf3 d6 (Fischer's Defense to the King's Gambit) 4.d4 g5 5.h4 g4 6.Ng5?!, 6...f6! 7.Nh3 gxh3 8.Qh5+ Kd7 wins a piece without too much trouble. But be very leery of ...f6 - it weakens Black's king-side, takes away the king knight's best square, and does nothing for Black's development.