As I understand it, James is saying that due to the small sample size of 'clutch' at-bats per year and the high amount of luck involved in every at-bat, it is impossible to compare yearly 'clutch' numbers - there is too much luck involved. Exactly, there's way too much variation for performance in 'clutch' situations to be predictive or more than an afterthought in player evaluation. That's not what he's saying at all. He's saying that all studies to date have failed to prove "clutch" AND have failed to disprove it. James believes the methods used to determine if clutch exists were flawed. He seems open to the idea that someday there may be a study that proves clutch, but the right metric has yet to be discovered. Sorry, I was referring to noisesquared's comment below the quote, I had already read the article previously.