show me how people who can only be narrowly interpreted as Popperian outperform people who are not Popperian

Show it how? I can conjecture it. Got a criticism?

Yes. There's no reason to conjecture this other than your own personal preference. I could conjecture that people with red hair perform better and that would have almost as much basis.

(The mere act of asserting a hypothesis is not a reason to take it seriously.)