Tristram: In lower left corner, after 1. e3 2. d2, 3.f4 is at least as good as 3. b5. After 3.b5, 4.f4 5.e4 6.e2, W has to decide whether the c4 stones are worth sente.
d4rkm4tter: There is a typo in your sequence, but your question is if e3-d2-f4 should be correct too. Continuation would be b5-e2. If we assume that both sides are equally good, I prefer the correct solution, because it ends in sente or black walls off both sides.
There is a typo in your sequence, but your question is if e3-d2-f4 should be correct too. Continuation would be b5-e2. If we assume that both sides are equally good, I prefer the correct solution, because it ends in sente or black walls off both sides.