Just got back and I think I figured out the routes:
Epcot - BWV - BC/YC - Swan/Dolphin - MGM
MGM - Swan/Dolphin - BC/YC - BWV - Epcot
So if you just wanted to go to Epcot, there's no stops in between, but if you're wanting to go to MGM, then yes, a walk isn't so bad.
In fact the boat captains, almost recommend that BWV'ers get off at Swan/Dolphin, and walk to their resort.