Too long a draw can cause inconsistent torquing left/right in your form. When you are too long, like BG said, it make for inconsistent bone to bone alignment. You release hand is more likely to change point either closer or further to you face, causing you to torque the bow to line up the sight through the peep.

Definately check into nuts&bolts on AT. You might find TONS of form flaws that you may be able to work on. Just take the time, and figure them out one by one...

Heres a direct like to part of his tuning pages.

http://www.archerytalk.com/vb/showthread.php?t=685228