It just keeps coming up, doesn’t it? The concept of a perma-long weekend with no reduction in pay. It's so attractive in theory that we as a society refuse to let it go. Not that we should ... keep fighting the good fight.

Dozens of companies in the U.K. took part in the world's largest trial of the four-day workweek. And a majority of supervisors and employees liked it so much they've decided to keep the arrangement. In fact, 15% of the employees who participated said “no amount of money” would convince them to go back to working five days a week.

And the idea appears to be gaining momentum—at least in some circles. A Ernst & Young study surveyed more than 500 U.S. C-suite and business leaders across a range of industries, and found 40% have either started using a four-day workweek or are in the process of implementing one. But another study out of New Zealand found that after moving to a four-day workweek, work intensified—as did pressure around performance management. And some experts have noted that employees already can have a hard time disconnecting, so they question whether a four-day week will help.