Its always been something to wonder about. In the Military as long as the turbine is cooking they log time, and if two are in the cockpit they both log, although only one is supposed to log PIC.
I have seen at least two Chief Pilots,with low time, find more than a few hundred extra hours in their logbooks. Nobody really cares, it sort of goes to the integrity of most Helicopter Pilots. I know of one Pilot who claimed 13,000 hours. He couldnt even pass a Company Checkride. AND he had an ATP, CFI etc. So I guess its the old saying. "Fly what you have too, Log what you need."