I was super in the other camp. Could not sleep if something wasn’t finished. Especially for coding. For marketing I found a (good) blog post can take a couple of days.
"Understand it in my head" is often a good stopping point too. Because if i actually go and fix it, i may find out i was wrong and spend even more time re-analyzing the issue to reach a new understanding.
Not good sleep but I would seem to be more ‘tuned’ in on the subject.
It kind of flows into the author's other point, "if I’ve got it, use it."