Good hitters are good hitters and weak hitters are weak hitters regardless of the game situation. But there is no reason why a weak hitter shouldn't be fortunate enough to get a series of fat pitches or good swings in crucial situations. Given enough time, this might even happen over some player's whole career. Maybe luck was the basis of the reputation of a Henrich or a Reese as a clutch hitter-but let me hasten to add that Henrich and Reese were certainly exceptionally good hitters simply on the basis of the quantity of their hits, as well as, perhaps, the timeliness of their hits. 

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