I’ve been working 4 days a week informally for a decade. Everyone checks out on Fridays with the exception of the rare fire.
I suspect it’s the same for other information workers.
I suspect it’s the same for other information workers.
But, crucially, we're all still present or within arm's reach. It seems more likely that we'll get 5 short days rather than 4 long ones so that everyone is on hand should things arise while, at the same time, acknowledging that long days become quickly inefficient.