While I somewhat agree that +/- might not be the "best" way to judge a world, everything dmurph said is true about fielding. Coop doesn't have good fielding(and, as a result, good pitching) because of player generation. Since Day 1, owners have valued the guys that can play the field. So the players that rot on the inactive list in some worlds actually get some playing time and develop in Coop. Far too many worlds have far too many owners who play a guy "up" a position(3B at SS, 1B in LF, DH at C, etc, etc) rather than down one because they want that extra bat in the line-up.