I've seen Chessmaster do the same thing, where it gives a blunder alert and then tells you to make the same move anyway. My guess is that when it detects something above the threshhold, it then does extra analysis but doesn't double-check if that changes the evaluation of whether it was a mistake in the first place.
The chess analysis computer is an idiot

I've seen Chessmaster do the same thing, where it gives a blunder alert and then tells you to make the same move anyway. My guess is that when it detects something above the threshhold, it then does extra analysis but doesn't double-check if that changes the evaluation of whether it was a mistake in the first place.
The one analysis was a howler, but there were at least half a dozen that left me scratching my head. I'm sticking to Fritz for real analysis for now.
I found this on pretty funny. On ,ove 13, I play Bxc1. The computer analysis gives this a "?". I am intrigued as I am not sure what would be better. So I read the line the computer thinks is better, and it starts off with Bxc1. Thank you computer for your brilliant analysis.
Overall, the computer decided 44% of my moves were mistakes despite my checkmating in 32 moves, with most of the "mistakes" being where I chose a line where I was only up by 8.4 pawns instead of 8.9.
1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. Ng5 Qxg5
5. d3?? Qxg2 6. Kd2?? 6... Qxf2+? 7. Qe2 Be3+?
8. Kd1Qxe2+ 9. Kxe2 Bxc1?