Earlier quoted context omitted.
> I'm pretty sure the gradient of all input-to-output curves becomes negative at some point, and don't see any reason why that point should be exactly 40 hours a week Tbf, it's the 4 day workweek advocates explicitly making the claim that everyone's output curves become negative on the fifth day such that 32hr output ~= 40 hrs output. Legal restrictions on working hours weren't put in place with the assumption that f…
Anybody advocating a specific n-day workweek, whether n is 4, 5, 6, or anything else, is probably going to claim their system has advantages related to productivity. The argument can be more complicated than just "the company will be more productive." Examples are "society will be overall more productive" (because the free time will be used productively), or "people should be allowed to work more hours if they want"…
The experiment being discussed here literally sets workers the target of achieving the same output as they previously managed in 5 days.
Sure, some people prefer 4 day weeks and happily take a pay cut in return and some people want government intervention to give them a better deal, but - unlike the 5 day week - there is an explicit productivity claim by many 4 day week advocates being assessed here