The teams with higher OBP do score more (on average) than the teams with the low OBP. Trying to pin the run scoring (or the run driving-in) down to individual players has all the difficulties already mentioned. But all else being equal, swapping out a low OBP player for one who gets on base more, should help your offense, regardless of how "clutch" you think his contributions may be. / I realize nobody has used the word "clutch" in this thread so far, but I always imagine that word to be lurking in the shadows in such discussions. Forgive me if I'm wrong.