I would absolutely trade off Matt Moore. I think the theory that it would send a bad message to the locker room is not a sound theory, because Moore is a backup. He lost his battle to win the job, and the team all believe in Ryan Tannehill now since he's performed so well. I might agree with the theory if Tannehill had not won over his teammates yet, if there were still some guys holding a candle for Matt Moore, but that's just not the case. It's really not. The players know that this is a business and when you're in the place Matt Moore is in, you're liable to be shipped off. That's just the business. It says absolutely nothing about the team's hopes for the 2012 season to trade Matt Moore off.
I'd do it for whatever price you could get out of Arizona. Then I would call up David Garrard and see how his knee is doing, see if he's willing to pick up a few pay checks for riding the pine. He knows the playbook, he's got chemistry with the players, and he's now healthy. They made sure he was healthy before they cut him.
Ryan Tannehill does not strike me as the type of quarterback that is an injury risk. He gets the ball out quickly, he's mastered the system of protections, checks and calls at the line, he doesn't try and do whacky things with the ball in his hands from a running standpoint, and he's always had a great pocket sense. He's an oak. At the risk of jinxing us I will say that the odds of him getting significantly hurt aren't that high (knock on wood).