A load of bollocks.
Paid 24/7, even though in civvie terms it equates to pittance, we should work the hours needed to achieve what is needed.
If your staying behind for crap like sweeping the barracks/tank park then no, if it's essential work then yes.
I am currently working in a job where working hours are strictly looked at, I admit it is great not to work over the prescribed hours. On the other hand when work is needed people arent willing to put in the time, with whinges of, ''I have already completed my shifts this week.'' By the way being at a joint unit doesn't help.