What makes Glennon a bad QB... and can that be overcome?

Suppose Koetter, based on his statement that you don't have to have a "franchise QB" to win games, decides that he can run an effective offense with Mike Glennon. Now, if he suppose that (and no, before anyone jumps to any conclusions, I have not heard that this is the case) then I'd like you guys to tell me what you think makes Glennon a bad QB. If you like Glennon, how about tell me what you feel like his weaknesses are? And finally, can those things be overcome with new and better coaching?Now please, if possible, I'm hoping that we can keep this thread somewhat civil and not bash one another over whether they like/dislike Glennon. Let's see if we can have some intelligent discourse on the matter.Thanks (in advance).