I would agree that on the surface it would appear that this is not even a debate...Sproles hands down. However, if I speculate...

Reggie was so good coming out of college. It's like someone said, "Sproles did everything we expected Reggie to do!" Is it possible, though, that Reggie has been heavily accounted for ever since he came into the league?

Is it possible that with everybody paying so much attention to Reggie, other players were allowed to flourish, like Colston as an example. To take it a step further, is it really stretching to say that once people started paying attention to the other guys after Reggie left that they were able to do some of the things they always wanted to do with Reggie but couldn't because they were paying so much attention to him being on the field.

I think that another poster said that we might have a clearer view a couple of years later, but since RB's have such a short career expectancy...we just may never know.