I remember DJ Hump wearing his jersey so you could see his midsection when others like Elam and Evans were doing it. I always remember wondering why an OL would want to show off his stomach. I never liked it from any of them and if I were the coach, I wouldn't let players do that in a game. As for OL, according to my thinking, they are either too fat to be attractive to women or they're not big enough and are displaying "their failure" to achieve the right weight.
I say all of this and follow that rabbit trail to say, I suspect that physical appearance was important to him and he didn't care as much about winning or the team as he did about looking a certain way. Now, it matters differently and I suspect he's willing to do what he ought in order to make a serious go at the NFL. I'm only speculating, but it's an angle that hasn't been stated. I understand and agree with the idea of easier off-season weight-gain too. Regardless, I don't lay this at Muschamp's feet.