lichess.org/analysis/r7/PPR2pp1/k3p3/3pP3/1P2PP2/8/5Brp/4K3_w_-_-_0_42Using this position, stockfish says that it is better to not take the rook. I have gone through the engine lines and can’t seem to find a major difference.
You need to do the follow up. After white queens, regardless of the square. Black also promotes and will sac the rook to continue with the checks.
The difference is that if you queen on a8, there will be a perpetual check since the b4 pawn will fall (with a check) and its unavoidable.
If you promote on b8, b4 won fall, and the waves of checks eventually run out, and white will have advantage.
Thanks, I just assumed black could continue checking and didn’t see the b4 pawn.
The b4 pawn is safe, thats it. There will be no perpetual checks as a result.
