Caddy did better. The Dolphins did better with Ricky solo then they did with Ronnie solo. Ronnie was the second best back on the team and didn't have nearly as big as an impact that Caddy had.
Caddy was more important to the Bucs AND he had better stats. This wasn't close. No matter how much more I like Ronnie Caddy won the title hands down.
If Ronnie would have played the last 2 games and got 100 yards a game(which is a stretch) to put him at 1100 with Caddy then it would have been Ronnie for ROY, but not by much.