On the fatigue issue: try pair programming. The day goes by a lot faster and with less fatigue for me. I was skeptical of the idea for many years, but once I re

On the fatigue issue: try pair programming. The day goes by a lot faster and with less fatigue for me. I was skeptical of the idea for many years, but once I really tried it I realized it was much better. On the time issue: employers in the US could hire part time developers. But I think good devs are so hard to hire in the first place that if you find one you want to have them work a full 40 hours per week to maximize their productivity (in theory.) It is unrealistic to expect 40 hours of dev time out of a developer who is working 40 hours a week, there's a lot of book keeping, meetings, emails, etc. to deal with. But if you cut the dev's time by 25% you're not reducing the amount of that non-dev stuff that needs to be done, so you're not making the time more efficient. Other than, as you said, perhaps reducing burn out. But that's what vacations are for.