Are you claiming a 4-day work week would result in less productivity? The article makes a good case for the opposite.

How do you explain the "paradoxical magic" in the final third of the article where, in every historical case of shortening work hours, "management was surprised to discover that output actually increased — and that expensive mistakes and accidents decreased"? Or the recent example of the Boston firm that took a day off in the middle of every week, and whose clients "reported an improvement in service"?

Are there any examples of companies going to a 4-day-week and reporting decreased productivity?