Leinart preferred to checkdown because it seems he doesn't want to throw int's mostly. Kolb checks down because he can't keep his eyes up long enough to find anyone, otherwise I'm sure he'd want to throw more down field than Leinart.
Really good point. Leinart played not to make mistakes, which led to little success. He had his injuries, which I think ruined him overall mentally, but didn't seem to change the way he approached the game.
Kolb seems to get more and more panicked every time I see him play. I once compared him to a chicken with its head cut off, but it's almost worse than that. It's like a chicken with its head cut off that has a feel for where the trouble is and wants to run TOWARDS it. I have never seen a QB generate more sacks than Kolb by leaving the pocket and running AT the pressure. It is maddening. With the way he creates sacks and kills drives, he'd be a great defensive player.