I've not worked at a hospital, but I've seen people in somewhat similar circumstances: military exercises, working as leaders at a youth camp -- and while they all get the job done, it's always been clear that they'd do a better job if they had more free time/more sleep -- in short they can work productively (under high strain/stress) for more than 8 hours -- but they'd do better work if they could work fewer hours.

I'd be surprised if the rate of errors didn't go down with work hours (to a certain point) at hospitals as well. And/or patient satisfaction went up.

To put this into (made up) numbers, if we assume that a software architect works either 12, 8 or 4 hours a day, and that at 12 hours a day produces on average 200 "valuedollars" per hour, that's 2400 vd/day. Is it really a stretch to claim that you could, on average, do 3 times better if you only had 4 hours, rather than 12? Paying 3 people 600/hour to work 4 hours a day, you'd get 3 times the value/day (note: note value/pay -- but we all know deadlines are important in projects).