In a very general sense (there are always exceptions), it strikes me that transitioning TSs who want to be stealth, in addition to the muscle loss as the result of HRT, might be motivated to lose or not put on weight in order to fit better into women's sizes for their height? And so there would be fewer instances of gynecomastia, which is likely what many CDers have, who say they have "natural" breasts when they are not on a strict hormone regimen?