There are boards that can be used by big guys and there are boards designed specifically for big guys. The Edge is in the former category. So you don't need to worry IMO. You aren't exactly a flyweight.
The subtext to DJ's post is that it is all about the paddle power that the rider can create rather than their weight. Over a large sample of people one might expect some relation between these factors but perhaps not so strong a relation that weight is a good guide to paddle power in any one individual.