Sample size large or small does nothing to prove or disprove clutch. In fact, the larger the sample size, the more normal those pressure situations become. Players can acclimate and adjust to those situation the more often they encounter them. Jeter had so many post season ABs that I am sure the adrenaline rush wore off many years before he hung up his spikes. I think a player who might have been a choker can become a clutch player from experience those situation over and over. Also, some guys are clutch from the start and don't need the additional reps.