Human beings are only capable of sustained attention for limited periods of time, plus they have biological needs and must navigate a physical world.
Now, if you're just talking about time on the clock, then sure- 168 hours is the limit per week. But we're talking about people doing productive, mentally demanding work. 80 hours might not be possible.
Medical residents routinely do close to 80 hours, and I would argue on average a small single digit number of those hours are unproductive. My SO is an OB resident and worked over 90 hours last week, and probably 75 of that was either in surgery, reading, studying, or giving a presentation of one form or another. About half of her weeks are above the 80 hour limit.
It's definitely possible. Just because we don't want to do it (I don't either!) or that it has negative long-term consequences doesn't mean it's not possible.
I'm aware of the legal limit and every single resident I've met has broken it at least once (really at least a couple times every quarter). The "good" programs will at least not require their residents to lie about it.
Human beings are only capable of sustained attention for limited periods of time, plus they have biological needs and must navigate a physical world.
Now, if you're just talking about time on the clock, then sure- 168 hours is the limit per week. But we're talking about people doing productive, mentally demanding work. 80 hours might not be possible.