but I'm fairly sure the Helmand Hilton did not have a special quiet suite for sensitive aircrew types
Not sure you are right about that - crew rest and fatigue was an important issue.
"Fight as you train, train how you fight", is a tired trope, but it is still as true today as it ever was.
Not if it means flying when you are unfit to do so. There have been enough studies in recent history to compare the effects of fatigue with the effects of consuming alcohol - both are insidious and difficult to detect during their onset, especially by the sufferer. The days of the macho man flying 24 hours a day are thankfully behind us