I think they should make Jackson the starter but I'm not the coach.
I would like to see them just try Jackson for one game. Get him 25 carries and see what he can do. Everything Mercer said is true, but lets compare Jackson and Faulk in that game.
Faulk - 17 touches for 19 yards (13 rushes for 6 yards, 4 receptions for 13 yards)
Jackson - 8 touches for 32 yards (7 rushes for 29 yards, 1 reception for 3 yards)
Neither line looks great on the surface, but projected out for 25 carries, Jackson was on pace for 104 yards rushing. Against the tough Bills run defense. And let's be honest, 6 yards on 13 carries is terrible, no matter who you are playing.