My experience is that you can continue to mess with it one spoke at a time, or you can replace it. I have seen alot of this sort of things with commuters pushing 200 lbs and up, and carrying 15-20 lbs of stuff in rear panniers. I really am curius if 1). the weight is simply pushing what a traditional 36-spoke/700c-27" wheel will handle (thus the 40 and 48 spoke versions of old); 2). The un-sprung mass of the panniers is doing these wheels in; or 3). if the higher weights require more attention to build quality.