If you're like most people, somebone already does: your boss, who answers to "convention."

I'm assuming the Danish professor is framing his findings as a viable public policy assertion.

I don't see how a shorter work week prevents anyone from working longer, or even less than the minimum. There are plenty of people working more than 40 hours, and plenty working fewer.

The only that the 40 sets is the threshold at which workers attain specific rights regarding overtime, benefits, and other things.