I dunno...I just don't think that growth is that directly related to protein. I agree that you need it to grow, but EXTREME protein. I doubt it. If you look at most nutrition books outlined for athletes, including BB's and wrestlers. You'll find that they recommend UNDER 1 gram of protein/pound of body weight. see Power Eating by Kleiner, where she recommends about 1 gram per body pound for growth phases. Actually I think growth is more related to carbs or more so to calories. If you're eating 400 grams of protein..that'd equal out to 1600 cals from protein, not to mention the fat inculded in there. so, a rough estimate would be that if you are eating that much protein, you're likely getting above 2000 cals from protein and fat. Which, in the end, just ends up being high calorie once you factor in whatever else you're eating. Personally, I am now 230 pounds at around 13% BF and I grow like a weed on just 200 grams. and TONS of carbs. You're body just needs the proper cals to grow with all macro nutrients included. BB's have a habit of following the " nothings succeeds like excess" principle and I don't think it's accurate.