In my book "Attack with the Blackmar Diemer", I have covered the line in the Seidel hall attack 1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 exf3 5.Nxf3 Bg4 6.h3 Bxg4 7.Qxf3 c6 8.g4 e6 9.g5 Nd5 10.Bd3 Nxc3 11.bxc3 ( In an earlier blog, I indicated that 10...Nxc3 could be answered potentially by 11.00 ) Be7.
In my book, I suggested the thematic sacrifice 12.00 00 13.Bxh7+ Kxh7 14.Qh5+ Kg8 15.Rxf7 ( diagram ), but it seems black can escape with a draw after 15...Qa5 as white has no other chioce than accepting the draw with 16.Rxg7+ Kxg7 17.Qh6+
If white wants to play for a win, 12.00 00 13.Rb1 ( diagram ) might offer the best choices. But then the same sacrifice is again available in all lines.
a/ 13...b6 14.Bxh7+ Kxh7 15.Qh5+ Kf8 18.Rxf7 and black's strongest move ( Qa5 ) is not available anymore as the b6 pawn is in the way (+=)
b/ 13...b5 14.Bxh7+ Kxh7 15.Qh5+ Kg8 16.Rxf7 (+)
c/ 13...Qc8 14.Bxh7+ Kxh7 15.Qh5+ Kg8 16.Rxf7 (++)
d/ 13...Qd7 14.Bxh7+ Kxh7 15.Qh5+ Kg8 16.Rxf7 (++)
e/ 13...Qc7 14.Bxh7+ Kxh7 15.Qh5+ Kg8 16.Rf4 ( the sacrifice on f7 is not possible as white can deliver check on g3 ) and white has a draw. Obviously, 14.Bf4 is better than 14.Bxh7+, but it shows that the sacrifice is possible in all lines.
SO it seems like this is a very usefull sacrifice to be remembered !