Well, lets break down what you said.
Seems a simple enough statement. Body = 0 lbs.
Wait, so now the body weighs something?
Okay, so maybe you're trying to say you don't move a significant amount of weight up.
Even using your numbers (which are grossly high in some categories, for example frame is about 1/3rd the weight you give), you have a total sprung weight of 4700 lbs. Of that, 700 lbs is the body.
So that means that you're raising...wait...can't be right, 14% of the body weight up? Hmm, I think that might count as significant.
And more realistic numbers are closer to:
Frame 500lb
Drive train 1500lb
Bumpers and sliders 600 lb
Body 1000lb
That gives you 3600 lbs of sprung weight, which means the body is....27% of that weight.
Hmm.....guess 27% might be considered significant. And increasing the height of almost a third of the total weight would affect CoG, and quite significantly.
So it goes back to a body lift raises CoG, but about a quarter the amount that a suspension lift does. So (very roughly) you could do a 3 to 4 inch body lift for the same weight penalty as a 1" suspension lift. (It's not linear, but close enough for web wheeling.)
FWIW I'm a huge BL fan (for 1-3" lifts, not stupid large ones). And I think you gain a lot more benefits from splitting your total lift between a suspension and body lift, than you do by a pure suspension lift. But trying to claim that a body lift "doesn't affect the center of gravity" just makes body lift proponents look foolish.
