(just for kicks, if you worked 10hour days for 7 days a week that is only 70 hour work week... doctors work at least 12 hour days, and usually 16 hour days to get to the full 80 hours!)
Oh and as far as weeding out?
Most 'weeding' out happens first and second year of medical school. In my class alone about 10% of the class failed first year exams, and they were forced to repeat or retake the whole year. (which SUCKS when you just paid $37,000 for a year of school that meant nothing). Then Second year weeding happens again with STEP1 licensing exam:
"Overall pass rates for first time USMLE Step 1 test takers are: 92% for U.S. M.D. medical school graduates, 81% for U.S. D.O. osteopathic medical school graduates, and 73% for international medical school graduates" http://en.wikipedia.org/wiki/United_States_Medical_Licensing...
Fail a year or a board exams? You pretty much can only be a psychiatrist or family doctor with little or no hope of every specializing.
My SO is a medical resident. They really are placed in unstable situations (to use a math/physics term). They are required to work 80 hr/week. If they report working more than 80 hr/week they get into trouble for a duty hours violation and yelled at for being "inefficient". If they report less than 80 hr/week they get in trouble for being slackers (a.k.a. "unprofessional", actually that's a catch-all phrase for anything the speaker doesn't like). No serious thought seems to be given to increasing staff levels.
And that's the problem (not your problem but the profession's problem) - the hope is to specialize whereas being a family doctor is the booby prize.
Well I know abut family but why psych?
I know one person who dropped out, but was at married to another resident, so has a safety net. Another resident dropped out due to a medical condition that prevented him from standing for hours a day and landed a job at McKinsey. Another friend dropped out and became a receptionist! Eventually she went into a residency for a lower stress specialty (surgery -> psychiatry).
The only area that learning how to deal with sleep deprivation would be a benefit is surgery and critical care areas (ICUs). But then again, if you could schedule things better and get more doctors in, maybe these doctors don't have to learn how to function on 5 hours of sleep.
I think you're right to the extent that the current medical service system requires doctors to learn to sleep less and less while functioning on an acceptable level (note that I didn't say satisfactory or even exceptional). But I think that's begging the question. Shouldn't we be able to change the current system and allow doctors to focus on building skills/knowledge, not the ability to function without sleep.
tl;dr: sleep deprivation is not a necessary part of being a doctor if we change the system, so saying that doctors must learn how to deal with sleep deprivation is a circular argument.
http://www.npr.org/templates/story/story.php?storyId=1135711...
Frankly, I'm surprised that as many doctors make it through - the working conditions are pretty terrible. Maybe the pay makes up for it, but you only get paid well once you get out of your residency or fellowship.
Better conditions will probably produce better doctors, not subpar doctors.
EDIT: Applied s/two/too