The Schuhler Gambit is a line in the Sokolsky Opening:.
[FEN ""]
[Date "Who cares"]
[White "White"]
[Black "Black"]
[ECO "A00"]
1. b4 c6 2.Bb2 a5 3.b5 cxb5 4.e4
White gives away histheir b-pawn here. Stockfish claims this actually gives a small advantage to White, (although I analyzed only to depth 25) while bxa5 gives a small advantage to Black.
Why is it good and what is White's plan?