I've made pretty good gains (at least I think so) doing Crossfit. I've gone down in weight from 200-205lbs to 180 or so.
And while I don't think I've plateaued, I do firmly believe that you need both diet and exercise to make the maximum gains.
Therefore I'm going to start incorporating a zone diet approach the same way I did crossfit: one little thing at a time.
I think a lot of diets fail because it's the equivalent of going "cold turkey". One day it's pizza and the next day it's bean sprouts and you try and gut it out. Well, that doesn't work. I found that I could handle small changes without feeling deprived, and that's the trick. For instance, I checked to see if I could go without cokes in fast food places, and sure enough, ice tea or water worked fine. Of course there's the matter of the burger and fries, but we'll deal with that. ;-)
Coach Troy has sent me some diet jumpstarts and I'll get on those.