I watched him botch a couple this year, and as A non-Cubs hater(sorry), I watched him in SF a bit too. Regardless, you may be right as far as one not being a better bunter than the other, but if he was just going to put Graffy in in the bottom of the ninth anyways, why waste Rios in a sac bunt situation? He might have been needed later in the game.
Probably because of a lack of confidence in anyone else. What is everyone screaming if he puts Graffy in there again and he fails again? Then you call JM the dumbest manager on earth.
JM is HORRID