The point is though that you have shifted your daily equilibrium, and it takes zero thought to maintain that. Choosing to eat 60 calories less a day is a choic

The point is though that you have shifted your daily equilibrium, and it takes zero thought to maintain that. Choosing to eat 60 calories less a day is a choice, which takes mental effort. In contrast, once you have that 10 pounds of muscle, it is burning away regardless. 60 calories * 365 days = 21900 calories a year. Fat has 9 calories per gram, so if you maintain your eating at the same level, that's ~2.4 kilograms (~5 pounds) a year you are losing without even trying. Obviously in reality, your appetite goes up as well, but the point is that once you are muscular enough you have to actively try to eat more just to maintain your weight.