[apercu]

I have never been very productive when trying to do knowledge work for more than 4-5 hours a day and more than about 28 hours a week. When I start working 50+ hours a week my productivity drops below what I would have gotten done in a 20 hour week, Things become harder, you get less creative, you start brute forcing your solutions. You write bad code or documents. These are things you typically learn with experience.