I think you might need to throw in someone like Davis to sweeten the pot for Washington, but if they do continue to tank, this could be a very good deal for both teams.
I also think a deal based around Jamison could be possible as well, and may be more likely, because of Jamison's larger contract.
A trade that I saw proposed on another site that I could really see happening if they tank is Ray and Davis for Jamison and Mike Miller. It saves Washington a ton of cash, while bringing them back a couple good players who would actually fit in very well with their team. And for Boston, they get Mike Miller, who can step right in to Ray's spot, and Jamison, who would dramatically improve the C's depth up front.