Because his defensive scheme is not very impressive. Weeden had all day to throw and I ddin't see many blitzes, I don't understand this approach. Was Fewell anticipating a lot of screens? But the defense wasn't good at stopping screens either. Fewell never goes after the QB on 3rd and long situations and it has burned the defense numerous times already. If Fewell keeps showing his inability to adjust to the game time situations accordingly, and keeps going with a very conservative approach of his, it's going to be a long day vs. 49ers.