I think the e4 push is unjustified for more reasons than simply giving up a central pawn. Capturing on a6 for the fully accepted Benko lines looks more testing.
After 5. e4?! (not a big fan of this move) Nxe4 6. Nf3 g6 7. Bd3 black can improve on the odd-looking ...Nd6?! with either ...Nf6 (standard reaction) or ...Qa5+ (taking advantage of the uncastled white King).
My own idea (the computer hates it, it shows "minus 0.7", and I don't care)
The move is to play e4.
(it shows -0.7 but in the next 5 moves, the evaluation is about equal).
In the Blackmar Gambit you also give up a center-pawn, it's not the end of the world.
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What do you folks think? totally stupid of me? or possible?
(the e4 push, not the draw offer lol)