I'm dabbling in that now. I weigh 243lb. I eat 2200kcal on non training days and 2400kcal on training days. If we use the body weight x13 rule I should be eating 3159kcal a day. I feel that is just too much. So I am trying this and so far its working well for me.
I see what you mean though. If I want to be 180lb in a year, which would require 2340kcal I should eat that way. That is what I am doing presently and I'm not losing scale weight but I am losing body fat. If you look in my gallery you can see shots from February and then shots from a week ago. Nothing impressive but you can see a fat loss. Mind you in both shots I weigh the same thing 243lb.
I think with a person that is mobidly obese and tipping the scales near 400lb. Yes getting overall scale weight down is a concern. However folks that are that big, I would think anyway, would have body fat at or near 50%. Either way its no good to carry that much baggage.
I'm a total newb though, so this is really just my take on things that have worked for me. I'm interested to see what some of the big names have to say.