[Liquid_Fire]

I think the idea is that an experienced player would recognise this situation immediately (usually there is only one legal move because you are in check, or there is only one move that doesn't put you in check), or even ahead of time (knowing that their opponent's move brings them in check) and just play the only possible move straight away.

Of course a beginner would take some time to spot this, but it's unlikely you would confuse a beginner for a cheater, since a beginner will likely make many sub-optimal moves and spend lots of time thinking in general.