Yes. It was playing in slightly dumbed down with me sparring with it at nominal ELO mode about 2200. It was giving me a chance. But this sort of thing could easily occur in real game play and engines should be able to annotate it correctly without needing human intervention.Michel wrote:But in normal circumstances an engine playing black would not have played Qb2 in the first place. Did Fritz10 really make this move by itself?Not only misannotate games but also to be vulnerable to best move avoidance in game play if a partial repetition sequence can be forced. The Fritz10 engine played Nxg2 losing the queen to avoid moving it back to d4 and creating a phantom draw via Rc1.
I can see that is correct for the player who is losing or when there is near equality, but I don't think it holds for the side with material advantage. They must follow through the first repeat to avoid exactly this sort of glitch.In search it is allowed to consider a position a draw after the first repetition provided the earlier identical position is also part of the search. But this is not allowed if the earlier identical position is part of the game history.It looks to me like the logic should be that the side with material advantage should never make the final repetition, but must consider a first repetition in full to avoid this sort of gotcha. I was surprised that most of the engines I tried also quickly lost the plot even when the cache was preloaded with correct game continuation after Qd4.
Otherwise an obvious anti-computer tactic is to chase around a piece that can be forced back to its previous square to gain a fake tempo.