The only reason he hasn't put up great numbers yet is due to these small nagging injuries. For instance, while he is officially listed as playing 13 games last season the reality is more like 9 or 10. If he managed to play 16 games somehow at something near full health Roy would certainly grab about 80 catches for 1200 yards and 14 touchdowns or so.
It's a gamble, though. He probably won't make it through a season healthy.
The facts have no meaning.