I don't understand the '99th percentile' aside as a way to convince HN readers that the commenter wasn't cheating. Rather, I take it as an expression of person

I don't understand the '99th percentile' aside as a way to convince HN readers that the commenter wasn't cheating. Rather, I take it as an expression of personal pride (in the positive sense) that there was such incontrovertible evidence that the commenter had no need to cheat in the first place, told with the satisfying (but probably unrealised) hope that the people who unjustifiably accused the commenter of cheating were later aware of the top marks he or she achieved after taking the exam in person.