Leon Washington wouldn't help much at the running back position, but he is a great punt and kick returner. He's being let go in Seattle because they got Percy Harvin, who gives them a threat as both a returner and a receiver.
The interest level in returners is probably an indication that they aren't entirely confident in Jeff Demps - the Olympic sprinter who they brought in last off-season but missed all year after being placed on IR. Demps has returned to Track and is running with Team USA, but still maintains that he wants to continue playing football. The Patriots need a boost in their return game and after losing out on Josh Cribbs, it seems like they are trying to bring some competition there.
Bringing in Washington might also be a bad sign for Danny Woodhead's return, since the Patriots would have a huge stable of running backs. Julian Edelman is also slightly effected since he has been used as the Patriots punt returner, but he has value as a receiver.
Former Seahawks a...