> if you are truly just doing productive, meaningful technical work, beyond 3 full days most people can't do it. Ok but an important detail is the distribution

> if you are truly just doing productive, meaningful technical work, beyond 3 full days most people can't do it. Ok but an important detail is the distribution of those hours. You probably didn't do 7 consecutive hours of exhausting hard thinking work in one day, nor probably 3.5 hours across 2 days... you'll be able to confirm, but sounds to me like an important key part of most meaningful, intensively intellectual (or physical) work lots of people do is that those hours are more-or-less spread across the whole work week, so in your example, kind of 1h30m per day on a 5-day week or closer to 2h/day on a 4-day week. I would fully agree with the latter part of your comment. Even if you argue that you'd not get more than 3 days of actual work done during a week, it doesn't necessarily follow that your work week should have been 3 days long; more like your daily timetable should probably be shorter and you should not have to wait in your office, mentally tired and not being productive, until the clock says it's 5pm and so you can now go home.