I'm living your dream. I'm on 70% part-time, originally because of the CS degree that I'm working on in parallel (I originally majored in physics bevore pivoting to IT), but I plan to continue on part-time (maybe 80% instead of 70 then) after I have my degree.
When I originally reduced from 100 to 80%, during my next annual review, my boss was surprised that it didn't impact my apparent productivity in the slightest, which supports your theory: More hours have diminishing returns, but cost the same from the employer's POV, so it would be better to spread it out to multiple people.
Indeed, the part-time model has been gaining traction within my circle of colleagues (in Germany). Many of them are taking a day per week off to work on their private projects, or cutting away some hours to spend more time with their children.
When I originally reduced from 100 to 80%, during my next annual review, my boss was surprised that it didn't impact my apparent productivity in the slightest, which supports your theory: More hours have diminishing returns, but cost the same from the employer's POV, so it would be better to spread it out to multiple people.
Indeed, the part-time model has been gaining traction within my circle of colleagues (in Germany). Many of them are taking a day per week off to work on their private projects, or cutting away some hours to spend more time with their children.