4x10h 4 times per week, every week sounds horrible IMHO. I personally definitely can't be 20% more productive per day by working 2 extra hours.
This would only work if you clock in 10h on paper, but actually work much less hours from home where nobody tracks how much you actually work, but if have to actually clock in 10h per day at the office, plus commute time, I'll most likely just space out and watch the clock for the rest of those two hours. And then that extra free day per week would be to recover from the long working day at the office nullifying any advantage.
Healthcare workers often work on six-week rotations that average out to 37.5/40 h per week. The key word is average, because shifts are usually 12 hours and some weeks (one or two per six week rotation) are composed of 3 days on, 2 days off and 2 days on.
That's not something we should praise. It's probably why healthcare workers are so burned out and make so many mistakes leading to malpractice.
Maybe in certain healthcare cases, longer hours can be more tolerable when you're doing repetitive things you've already done a million times that you can do "on autopilot" without the risk of mistakes, but for mentally intensive tasks where you're constantly thinking and problem solving and need to stay sharp, there's no way I can pull 60h/week of productivity. I'm not even fully productive for the whole 40h, let alone more.
I could pull 60h weeks if I were working on my own projects being my own boss answering only to myself and working at my own pace and deadlines, but not part of the soul crushing corporate machine with constant bullshit interruptions, meetings, theatrics and management breathing down my neck.
There's a source somewhere for the greatest number of errors happening because of shift change, where e.g. a doctor's notes are incomplete and don't mark down a detail that later turned out to be important. The study found that much-longer-than-i-thought shifts were better than shorter ones, I believe e.g. 16 or even 24 hour shifts were safer than 8 hour shifts.
This would only work if you clock in 10h on paper, but actually work much less hours from home where nobody tracks how much you actually work, but if have to actually clock in 10h per day at the office, plus commute time, I'll most likely just space out and watch the clock for the rest of those two hours. And then that extra free day per week would be to recover from the long working day at the office nullifying any advantage.