[Vektorweg]

Some thinking-intensive work can bring you at the edge in just 3 hours a day. After that, you generate more problems than solutions. Especially mathematicians are prone to this. Similar cases in software development need to be respected.

[srtjstjsj]

3 hours of thinking-intensive work is fine. Then take lunch/walk/shower, and sit down to write documentation, update bug reports, chat with a coworker about your ideas, review someone else's code.....

[tw1010]

Grothendieck worked twelve hours per day every day of the week for a decade.

Source: https://math.stackexchange.com/a/874290/161054

[eecc]

Yeah we should all - at he miminum - outperform a mathematical giant.

[s73ver_]

Good for him. I have no desire to sacrifice all of my free time to make someone else rich.