Position after 7.d4!?!?
It seems crazy at first (as do a lot of gambits) until you look closely at the lines and realize that Black's pieces are kept from getting into play while White's develop easily and even his queen's Rook swings into action via Ra1-a3-g3 (since the Knight at f3 generally gets exchanged at d4 or leaps to e5). That seems worth a pawn to me. And best of all, Black is forced to deal with a wild tactical battle, which seems exactly what he is trying to avoid. As Steve Stoyko asks: "Why give him what he wants?"
The idea of the d4-sac a move earlier, as tried by Zukertort (included in the same game file), does not seem as attractive, but it is also worth a look. I actually have not had a chance to review Conquest's own notes in Informant #67, but I think I have identified at least one critical moment where White could have gotten real winning chances. Let's see if you agree:
White to play after 16...Ng6