Just because he's doing it doesn't mean he doesn't have anxiety (he may or may not, I just don't know). There's the "riding the lion" principle: A crowd of people is watching a stuntman do a performance of riding on the back of the lion. Everyone in the crowd is thinking, "Man, that guy is brave. I couldn't do that." The guy on the lion is thinking, "Man I'm terrified. I hope I don't die." TL;DR Ball size is not necessarily inversely proportional to anxiety. :)