In Crabtrees situation though, he had the same QB last year AND a horrible offensive system that had no direction. I think having a competent coach and offensive system will hike his numbers naturally. Fitz went from a great QB to a horrible QB so there was no place to go but down and still, he had a good year by most receivers standards. Just not a Fitz year.
I don't expect greatness out of Smith, but I will say that the guy hasn't ever had a combination of a good offensive system and good players surrounding him. He has both this year, so maybe, just maybe, he can be a decent (low expectations) QB for a season or two while Kap develops.
We can hope............