Why Did He Play That Move?

Once your opponent has played a move, it is always a good idea to ask yourself "Why did he play that?" Often the reason is obvious; sometimes, not.

HauntedKnight - amedved,
blitz, FICS, 2013

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 

4...Kxf7 5.Nxe5+ Nxe5 6.d4 Bxd4 7.Qxd4 Qf6

Why did he play that move?

Clue Number 1: 

White played 8.Qd1 in both Jerome,A - Norton,D, unfinished correspondence game, 1876 and Jerome,A - Jaeger,D, correspondence, 1879 (1-0, 35).

Clue Number 2: 

HauntedKnight, himself, played 8.Qd5+ twice in 2011, once in 2012, and four times in 2013.

8.Nc3 

The Database has only two examples of this move, and in both games Black responded with 8...Ne7.

Amedved has an improvement.

8...Nf3+

Oh. 

White resigned. His Queen is lost.