IMHO there is possibly another dimension which can be added to the conversation. Primarily if a doctor is feeling fatigued (not tired) he can quite easily step out of the room, possibly mention it to someone, ask to be replaced at that particular moment in time. Once you are airborne, you are committed to completing the task in hand. There is no option to remove yourself from the loop as it were.
The suggestions made about turning the autopilot off to wake up are frankly, well... ludacrous. Aside from the RVSM implications made, correctly, further up the page. People nod off all the time when driving, and if subject to too much fatigue, whenever and wherever they happen to be. To increase your workload at a time when your brain and body are telling you that it can't process much more information is asking for trouble.
With regards to managing your rest, again its a nice idea. But there are always external factors, that could prevent you from getting the required rest. Working a month of late nights and then having to condition your body to wake up at 04:00am for your first early is very hard work. Many people I fly with will readily admit that the amount of rest gained before the first early can be written off as they are pretty much resigned to the fact that they will be knackered in any case. I know on the eve of my first early flights I tend to lie there for 3-4 hours sometimes watching the clock tick round to my report time.
By categorising fatigue as an improper management of ones rest period, which sounds slightly rich to be honest, considering we don't get a break every 30 mins, the situation certainly won't get any better.
Rgds.
T