I just had a crushing pawn endgame and I genuinely forgot how to approach it because by 1 tempo it's a draw now. I didn't realize this and I won on time. I had a feeling b4 was wrong but I'm going to use this to study
If I had used the correct pawn move I could shoulder the king away and with best play I could essentially have a fox in the chicken coup endgame to run to the other side