Best line against Blumenfeld?
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The most ambitious is probably to accept the gambit pawn and hold on for dear life as black gets a strong pawn center and development via the move order 5. dxe6 fxe6 cxb5. The strongest line, in my opinion, is the positional 5. Bg5 which steers the game in a quieter direction than what black usually gets if you accept the gambit. Another interesting move is 5. e4!?, which I haven't done very much analysis on myself.
I'm kinda switching up my d4 repertoire, and although I've never played against the Blumenfeld gambit, I want to be prepared for it in case I come across it OTB. What is the most ambitious/strongest line against 4...b5?