I have a split lunch schedule -- I usually take 30 minute lunches during Mon-Thu and take an hour for lunch on Friday. Based on my internal notes (and a bunch o

I have a split lunch schedule -- I usually take 30 minute lunches during Mon-Thu and take an hour for lunch on Friday. Based on my internal notes (and a bunch of metrics) I am more productive on Friday (especially afternoons) than I am on a given Tuesday afternoon. There's a ton of other variables and probably some contraindications in that anecdote, but it's the kind of counter-intuitive result that a 4-day work week is based on. I'm also amazed at how variable an hour can be in terms of output. I can easily do 5-10x work at my best compared to my worst. The key here is being completely in the zone, and not trying to do it all the time. I believe a 4-day work week could help put more people in that productive zone,resulting in as much/more output for less hours spent. Of course, you have to have employees trusting enough and stable enough to use the extra time to decompress.