Sometimes dodgy openings still work

Despite my best efforts I can't seem to get away from my own dodgy opening repertoire. For example the Sorensen Gambit in the Advance French is known to be dubious, and yet every time I see a French 9.Ng5 gets played.
Of course it doesn't always end badly. In the following game I follow a great deal of theory, all the time wondering exactly why White would willingly choose this line. Then my opponent tried a new idea, and suddenly the position blew up in his face.

Press,Shaun - Berkley,Steve [C02]
Chessworld , 07.08.2010

1.e4 e6 2.d4 d5 3.e5 c5 4.c3 Nc6 5.Nf3 Qb6 6.Bd3 cxd4 7.cxd4 Bd7 8.0-0 Nxd4 9.Ng5 Nc6 10.Re1 Bc5 11.Qf3 Nh6 12.Nc3 Be7 13.Nxh7 Nb4N 14.Bb1 d4?! (D)
15.Bxh6! dxc3 16.bxc3 Nd5? [16...Bc6!] 17.Bxg7+- Rg8 18.Nf6+ Nxf6 19.exf6 Bc5 20.Bh7 1-0