theatlantic). According to this report the city wants to find out whether the reduced working time lifts the productivity enough to compensate for the less hours worked.
I think this experiment could be very costly. But it is just part of an ongoing long term trend. Since the industrial revolution the average working time has been shrinking amid rising incomes - thanks to the increasing productivity (output per working hour). At the begin of the 19th century the typical work day lasted anywhere from 10-18 hours per day, six days a week - and even children had to work many hours in the factories (today). I believe that rapid automatizing and the growing use of robots could reduce the average working time further and the trend might indeed go to the 6 hours average working day.
However, I would prefer keeping the average 8 hour working day and reduce the working week to 4 days. This would save the cost and trouble for commuting.