Agreed, 3-4 day work weeks sounds better all around.

Less commute time, more time to pursue hobbies and take trips.

I bet 4 * 9 hours days would have a negligible impact on worker productivity and reduce costs like heating, cooling, lighting, since offices would be closed an extra day.

Yes, I'm with you. I would also value a larger block of days off each week as there's more potential for trips etc.

A six hour workday would be 30 hours a week. Imagine that as three ten hour days instead. Wow, that would be fantastic.

Well, I think the benefits of the 6-hour day would disappear then. IIRC correctly research shows that productivity falls steeply after 5 hours at work, with hour 6-8 being at 75% producitity, and after that 50% (approximately). So having 3x10 days would kill the benefit of increased producitivity during the time you are at work, while still costing as much.

As a policy, this sort of thing probably would not work but the statistic does not apply to all people. I'd be interested to see a large company which allowed the workers to decide freely. Measuring results would obviously be difficult.

For me, when I work has a much, much bigger impact on how much stuff I get done than the number of hours I work.

I'm not a morning person, yet my job has me coming in before 8:30 so I can attend morning standups (ugh). Right after lunch though, I can easily get in the "zone" and do a ton of good work.

I'm exactly the same. I get in the zone everyday, and 10-12 hours usually blows by like it's nothing. Glad I have a job where there's always (fun) development work to do...I don't understand how 6 hours a day could ever be enough though

5 -6 hours uninterrupted work would be nice. I reckon I must get interrupted every half hour or so.