I wouldn't count out Tann quite yet, although after this weekend people seem to be ready to start deifying Iowa guys again.
I didn't see the match with him and Perry this weekend, but Perry has shown, weight cutting, motivation or whatever that their is a strategy to beat him.
Keep the distance a little bit on the feet, and defend that little superduck/high crotch shot that Perry takes from way, way out. And then most importantly when you shoot on him you've got to finish quick. In the match Tann won last year, his first TD he finished quick, and in OT when he hit his move for two and two he won a scramble. Perry is too good from the crackdown position to dillydally when you bring him down to his butt.
They both rode each other last year in the match again that Tann won, I didn't see the other one.