Batting 4th is actually HUGE in terms of RBI opportunities.. compared to any other slot. I think it's over 2 RBI opportunities per at-bat (avg of >1 on base plus yourself) in the first inning alone.
bat position is still quite important... the #2 slot is a VERY underrated slot.. if you place a good hitter there, he'll produce GREAT numbers.
Look a Luis Matos, Marcus Giles (when he was playing well), Durham last year for the White Sox.
The key to Fantasy Sports is NOT about Sports but rather the "manipulation of numbers" in your favor
MASTER THOSE NUMBERS