Not that I think it would happen, but... say Tyrod is not ready for the beginning of the season and Peterman gets the nod week 1. He does well, and wins. Maybe Tyrod needs another week, and Peterman wins week 2. How many consecutive wins would Peterman need before he passes Tyrod as the starter, in the coach's eyes, and remains the starter even after the original #1 returns, ala Romo-Prescott?
Not saying Peterman has those skills, though.
But it sure would be great if Peterman really was The Guy, and we could spend two 1sts, two 2nds, and possibly 3 3rds on building pieces around him, instead of using it as trade-up ammo to get The Guy.