I was recently playing a game as black against the Ponziani when this position came up. (I recommend you flip all the boards to show from black's perspective)
Here's the beginning of the game:
[fen ""]
1.e4 e5 2.Nf3 Nc6 3.c3 d5 4.Qa4 Bd7 5.exd5 Nd4 6.Qd1 Nxf3+ 7.Qxf3 Nf6 8.h3 e4 9.Qe3 Bd6 10.d3 O-O 11.dxe4 Nxe4 12.Bd3 f5 13.Bxe4 fxe4 14.O-O Bf5 15.c4 Qf6 16.Nc3 Rae8 17.Bd2 Be5 18.Qg5
In the starting position, both sides are apparently equal (0.0)
[fen "4rrk1/ppp3pp/5q2/3PbbQ1/2P1p3/2N4P/PP1B1PP1/R4RK1 b - - 6 18"]
1... Qb6 2. Bf4 Bxf4 3. Qxf4 Bxh3
After 2.Bf4 black has apparently made a blunder, putting me 90 centipawns ahead. In the game, I spent 5 minutes debating between Qxb2, h6, and Bxf4 finally choosing the last, seeing it as the simplest most effective option.
Apparently, Bxh3 was a blunder on my part, putting white ahead 90 centipawns. (So this move helped white by 1.8) Only, I cannot understand why? I ended up winning the game with the following moves.
[fen "4rrk1/ppp3pp/1q6/3P4/2P1pQ2/2N4b/PP3PP1/R4RK1 w - - 0 21"]
1. Qg3 Bd7 2. b3 e3 3. fxe3 Rxf1 4. Rxf1 Rxe3 5. Qf2 Rxc3 6. Qxb6 axb6 7.Rf2 g6 8. Kh2 Bf5 9. Re2 Kf7 10. Rb2 Rc2 0-1
I feel like the decision to play Bxh3 was justified and what helped me win the game. Yet the engine disagrees. Could somebody tell me what the problem with Bxh3 was?