As far as not moving back to WR...he was the best corner on the team coming out of Spring camp. Anderson couldn't beat out a Freshman corner, so it worked out nicely to put a Senior over in the WR group. Teague was much more valuable as the best corner available when Waggner had to be emergency-moved to FS.
As far as being demoted at CB...while he's playing about the same as he was in the Spring, other teams have found out his weakness. He's still a good zone corner, but he gets beat deep playing close to the guy. I'm not saying he's regressed, but the other guys (like Izzy and Coleman) have gotten better. The emergence of Randolph as a play-maker and emerging eraser meant Waggner could move to his best position.
To use a Dooleyism, this is just Darwinism at work. Teague's a little bit down, other guys are a lot bit up. Same thing for Gordon. If he was playing better all the time, he'd already been in there.
I'd say there's 0% chance that Teague moves to WR, this year or next. He's gonna be an experienced, talented, Senior next year. That hasn't happened in a long, long time. It's something the program needs.