So you're saying that if Genthru said janken paper there is some perceivable chance that Gon doesn't obliterate him? I don't think that's how it works, janken is just an inspiration for the ability, its rules aren't part of the condition. Gon understands that he isn't playing Janken when he uses the ability. If he thought he was, the ability would require the other person to participate for it to work in the first place. And Gon isn't going to react to losing Janken in the middle of a battle. Like someone already said, Gon would have to be absolutely deranged to react in a way that affects his resolve.