My experience is 4-10s work IF you take a break in the middle of the day. An actual break, not a lunch at your desk break.

That was my experience as well. I'd use my lunch break to go to the gym in our building, and eat a protien shake or something at my desk.

Given the diminishing returns of hours worked in a day, I'm guessing business outcomes would be somewhat worse for 4/10 schedules, at least in fields where productivity varies.

I also bet, business outcomes would be improved on a 4/8 for 80% pay system. At least some of that work output on the lost day would be shifted to the other 4 days--since work tends to expand to fit the time allowed.

> Given the diminishing returns of hours worked in a day,

Without a study of white collar productivity decrease from a 4/10, I cant accept the statement as a "common sense" premise.

I do better remote sitting on my coutch until dinner programming away and write off fridays...because nobody notices that most of the organization becomes nonresponsive after standups at the end of the week.

If your work doesn't actually matter to the business then any amount of it is a loss, since have to pay you but don't get anything back.