The Rams are in a "develop the young guys" year. Time for the 2nd and 3rd year guys to step up and start or contribute in their unit's rotation.... or move out. Lots of time is going to be given to the rookies that seem to have what it takes to develop. What would be the point of taking up an extra roster spot with Rypien? The Rams have little chance for the Post season this year, and without Stafford it is hovering around zero. Rypien won't change that.
So if Stafford is out for a couple of games, I would think they want to give a guy with a possible future the reps, and not someone who has no future with the Rams. Especially since winning is not goal #1 this year.
I think from his history, it is highly unlikely that Bennet is going to soil himself. He's a gamer. As long as he listens and stays within what the coaches want him to do, and stays healthy, I think it is the most likely outcome that the he is QB2 and Rypien is QB3, but on the PS. If Bennet was sent to the PS, he'd be gone in a heartbeat.
Just my opinion.