guh.. i feel your pain Rob..i was doing 8am-6am mon.-fri. then an extra 2 hours on saturday.. it was terrible.. i'd fall asleep for only a few minutes wake up fully refreshed and not be able to sleep again for a least a few hours...a few consistant months of 10 hours of sleep a week will put you right above braindead.
How people do it for years, i'll never know.