I don't even think Lex really cares about the reliability of the "stats". He's only looking for information that agrees with his biased thinking. I can't believe how utterly one-sided his thinking is, is he really epitome of someone who is fair, objective and makes well informed decisions.
There indeed is a difference between someone's surface behaviour and their true cognitive abilities. And he makes the distinction between the true cognitive abilities of a person and their behaviour, or the way they express their intelligence. He added on a perosn's outward behaviour to his definition of intelligence and this is a faulty way to judge a person's intelligence. Einstein indeed did do ALOT of things that seemed to make no sense and he actively hated the strict rote learning of the german education system. He was very absent-minded and that can look pretty stupid to alot people, but when we look at his body of work, it is very clear he was a genius.