Endgame position

So I’m trying to figure out the engine at move 29. By this point I have a comfortably winning game, and I’m just cleaning up. The engine called 29. Rxh6 is a mistake, and says 29. Bxh6 would’ve been about 3.5 points better. Problem is, the bishop line includes multiple bad moves when I game it out in the engine, so I'm not sure I believe it.

Can someone explain what I’m missing here? I can see the bishop line would trade down Black’s pieces a little quicker. The knight wasn’t a threat, though, and the rook let me start cleaning up pawns and then threaten the king, so I went with that.

I just don’t see how that move could make a whole piece’s worth of difference to the outcome. Can someone help me out?

Do you mean 29.Bxc5 was the recommended move? This is what I would have played as it just makes the most sense. You are up an exchange, blacks only chance is to generate some counterplay. By removing the knight you lessen this chance as this leaves him with only his bishop sat in a bad spot behind his own pawns, you double his c pawns, you don't lose your e4 pawn, you are still capturing the black h pawns with your rook. All this good stuff. Your move is still winning, it just is not as brutally clinical as Bxc5. 

No worries. Always best to keep it as simple as possible in a winning position and snuff out any potential counterplay. Here is an example of how black could have made things more tricky for you. It's still winning but care would have been needed instead of things being very simple: