[megaduck]

I'm not convinced it's optimal! However, it's a "known good" number that's easy to convince people to follow along with. Running experiments is hard and expensive, so we just haven't tackled that yet.

My personal suspicion is that optimal is probably in the 35-45 range, but I'd love to have more data.

[otakucode]

It is "known good" specifically for repetitive manufacturing labor. That's what all of our business structures are optimized for. As work changes to be primarily mental, things will change. It's good that you're thinking about this sort of thing, it will give you a significant advantage in the coming years. Lots of research into how capable humans are of extended periods of mental exertion shows that we can be productive far less than with physical exertion. I suppose it's a good thing that thanks to computers, mental exertion ends up producing productivity multipliers rather than just incremental improvements then!

[Aeolun]

My suspicion is it's somewhere in the 30 - 40 range. For me personally my productivity starts declining after 30, but I'm fairly certain some of my coworkers can do it longer.