I've seen an interview of the actor and he says he's nothing like he's character. But you believe his character, you believe he's Robbie. And his work! The episode "Count on Me", where Robbie and Kim are forced to work together, the episode had alot of him, and it is truly my favorite episode. The scenes with Kim Carlsie, they played off each other so well, which not anyone can do.
Which is why, I truly believe, he could carry his own show.