Hospitals in this area are so short-staffed for RNs that the very notion of NOT paying them OT (that they've rightly worked) is laughable.
What IS done to limit OT is the hospital policy of not allowing anyone to clock in more than five minutes prior to a shift beginning, so that by clocking in say ten minutes early each day you don't end up with an hour of "unauthorized" overtime. Most people don't follow that, either, but then again, we're so short that if they paid an extra hour over the course of a week, who the heck in administration is going to annoy the nurse with it?
Overtime happens, and the more short-staffed, the more it happens. If I have eight or ten patients on my acute unit and it takes me two hours after my shift ends to complete paperwork, there's not even a squeak. Otherwise, they'd be even shorter-staffed