Katniss shrugs. Maybe if she actually cared to apply herself, she would have been better at school. And she would have been able to correct Buffy's mistake. As it is, whether Katniss actually knows the actual word (hubris) doesn't matter. It comes down to how little she actually cares about whether Buffy is right or wrong. Long story short? She doesn't.

Really, unless Buffy knows some way to help Katniss forget the glitched memories, there's probably not a lot she can say that she would care about.