I'm on board with the Stubbs thing as I've stated for the reasons above. However, let me say, I definitely don't see Dickerson as marginal defensively.
This year in center (sample size beware, obviously), he's a +35 UZR/150. That is incredible. Clearly the size of sample is as such it would come down if he actually played 150 games out there. However, even expecting that to come down, he's probably a significantly above-average fielder out there.