[saverio-murgia]

Here on HN I always read people saying that you are more productive working 5 to 6 hours a day instead of 8. According to the people claiming that, the people who got a 25% cut in working hours should have performed better thus accomplishing the same amount of work. That obviously did not happen.

[herrkanin]

I think it's different with physically intensive jobs, such as nurses in the trial, and mentally intensive jobs, such as programming etc. The latter may very well end up being equally or more productive, while physically intensive jobs probably would end up with reduced productivity.

[benchaney]

Well as another commenter pointed out, they had to hire fewer people than a naive man hours calculation would suggest, so their productivity did increase.