Preparing Nd1-e3 in order to exploit the blockading square on e3 in a more powerful way.
Preferable was 1...Bf6 2.Ng2 Ng7 with just a slight disadvantage – Trifunovic.
6...fxg4 7.Nxg4! Qxf4 8.Qxe4+! Qxe4 9.Bxe4+ Kg8 10.Bg3 with a big advantage – Trifunovic.
Now the e4-pawn has become weak, besides which Black has a constant problem with the passive knight on a6.