Fat under their shirt and/ or on gear mate if they out on the regular. You just can't keep lean and big if you are binging hard every week, its not possible
Tbh it is mate.
My pal was banging a ton of tri test for 15 weeks! and he was literally HUGE, crappy diet of just chinese/chippys, banging more t5's then you could even think of. He was ripped the bone, yet he went out 3 nights a week or more getting absolutely hammered plus taking tons of coke. Yet his size was unbeliveable, was only like 5ft 3 but was massive and ripped to shreds, that was early this year, and now he doesn't take any gear now, but is still in that condition all be it smaller and still has same life style. Got another pal who is exactly the same, massive and ripped but same life style. Crazy though! and not healthy. But it's possible.