There's some interesting scenes in "Rivals" if you know Bashir's actual racketball skills are much higher than he normally let's on. First, Bashir has to pretend to be "normal" fit young guy, who can easily beat the older O'Brien, and then naturally gloat about it. Then, later in the episode, as the "luck game" starts acting on him, he finds himself loosing the game, even when he tries. How can this be? he may be asking himself; I'm much better than O'Brien, heck, I'm even much better than O'Brien thinks I am. Because I normally have to bring down my game so that no one recognizes my enhanced abilities.
But the scene I find the most interesting and revealing about genetically-enhanced Bashir in "Rivals" is not the beginning, when Bashir is winning, nor the end, when he's loosing because of the "luck game", it's in the middle, when Bashir "throws" the match to O'Brien because he feels bad for him. Remember, genetically enhanced Bashir is always "taking it easy" on those people he plays games with. He has to in order to not let on to people the fact that he has exceptional genetically engineered abilities. And he has also gotten very good at doing so in such a way that it appears natural, not like he's trying to loose. It has to appear as if he's trying to win, even though he's not really doing his genetically-engineered best. In fact, he often chooses to throw in some gloating and pride, maybe because he's just young and feels like gloating, but maybe because he's trying to throw others off the scent of thinking he's actually capable of doing even more than he's showing (and gloating about). But in the match he's trying to "throw" to O'Brien there is another interesting dynamic. He now has to pretend to have even less skill than he normally shows, which is already less than his real skill level. And you know that Bashir could have done so in a convincing way. He's had a lot of practice at throwing games in a convincing way. (Unless he has gotten SO use to his new "normal" level that this further-reduced level feels weird to him.) Yet in the episode, Bashir acts so obvious when he "throws" the game with O'Brien. When he's throwing a game, which he's probably done many times, he does so in a very obvious way. Was this just because he really didn't want to bring his game down so far? Or was he acting so poorly so that others couldn't possibly question that his normal level of play wasn't also faked? I'm not arguing one way or the other. I just think it's an interesting question to think about.