Whenever I read one of these posts I'm always very curious about the age of the writer. I find my thoughts on this topic has changed a lot from mid twenties to mid thirties.
Hi! I'm the author of this post. I'm 22. I wrote most of this post when I was 20. I still agree with basically all of it. Also, I spent like 6 months writing it because most of the productivity advice is bs and wears off quickly and I wanted to make sure I only include things that stick.
... Without breaks. That's more or less insane. However that's easily adjustable, the article is the same if we read half that number.
It's the complete absence of influence of other people (be it in the form of SOs, kids, coworkers, office environments, meetings, bosses, customers, what have you) that makes it alien to me.
If I could have 4 hours of real, concentrated, productive work on important things each working day, I would massively increase the impact of my work.