Yeah, but that was before. I think they're saying after losing all his abilities and getting the injection, he can only do them one at a time, and he doesn't have the ability to re-access them. Again, I don't know why they think that, but it is several different people, which is why I thought I was missing something.

It might be the case. Peter and Hiro were too powerful (its okay for Sylar, because he's supposed to be the bad guy and thus more dangerous), so it might be a sort of reset button. Hiro loses the mastery of time and space (and now Peter has no one to absorb it from either), and Peter doesn't have all the abilities that should make everyone else a joke to him so they don't have to come up with BS reasons why he actually would run into trouble dealing with things.