Troup thus far has been a disappointment, but it would be foolish to toss him to the scrap heap at this point. DT typically takes a bit for collegiate players to learn, and often times it can take those players a few years to fully grasp their position. We're talking about a guy who played some as a rookie and then had his second year washed out by injury.
He may never develop, but it would be the height of stupidity to release him, especially when there isn't currently a realistic upgrade on the roster. At the very least, let him get healthy, bring in some competition, and make him fight for a job in camp next year.