I think one of the main benefits of a four-day workweek is having a regular weekday free, meaning you can easily do errands and things without having to take time off work or cut into the shared time of the traditional weekend where many things are closed and we have so many of our non-work social commitments. Were the four-day workweek to be mass adopted, I would hope we as a society would be smart enough to not all choose the same four days.
Yes, it would not be good if the same four days were selected. The third day should be free-ranging, because then everyone else is out too, which is irritating!
