Look, I don't think anyone believes TB would do a straight-up Henry-for-Barber deal. But try this on for size:
We trade Clements to Washington for the #9 pick.
We then take that pick and trade down for a package of picks, starting in the late first round and probably also including a second and a third or a fourth.
Then we take one of those picks, maybe even our original #55, and trade it with Henry to TB for Barber.
Washington gets a topflight corner/return man for its #9 pick. TB gets a starting running back and a second-round pick for Barber. We get an outstanding cornerback, a first-round pick, a second-round pick to replace the one we lost, and an extra pick in either the third or fourth round. And we lose (1) a guy who is walking next year no matter what (don't kid yourselves), and (2) a guy who is a lot more valuable to someone else than he is to us.
Flame away, but I'm just thinking out loud.