[blub]

If there are several good moves, it seems logical to cheat by not picking the computer’s top choice.

[agarden]

If there are three or four good moves of approximately equal strength in a position, then it just isn't a position where someone at grandmaster level needs to cheat or benefits from doing so. They were going to find one of those moves anyway.

[hrunt]

Is it cheating if you make decisions to purposefully not gain an advantage (ignoring gambling-induced outcomes, like throwing a match)?

"He was cheating! An outside influence was telling him which move to make and he purposefully didn't do it!"

[blub]

Like I said, it depends on the available set of moves. If #1 is +1 and #2 is +0.7, but the cheater wanted to play #5 at -0.5 then that’s an outcome-changing difference.

Chess engines like Hiarcs can show a series of good, ok, questionable and bad moves for each touched piece color-coded on the board for example.