Keg
A study would indeed be interesting
Remember they did one with UniSA several years ago? It was supposed to inform all sorts of interesting rule changes to deal with fatigue and included little wrist bands (today known as a FitBit) to record your sleep, sleep diaries and post-duty simulator sessions to assess your performance after a long duty.
That study went away, never to be heard of again and the results were never made publically available. Presumed they lifted a rock, didn't like the look of what was underneath it and gently placed it back, hoping that whatever was under there wouldn't escape.
Never lift the rock....