I remember Seth Godin saying once that every business book can be summarized in just a few pages but the book itself is a story. I think it goes beyond just that idea and is The Exercise in reinforcing ideas. Yes, you don't need to spend 10 hours to memorize an idea: _move fast and break things._ Yea, I get it.
But what does that actually mean? How do you actually implement that philosophy? How do you internalize it? How do you navigate situations where you will revert back to your old habit or philosophy? I think you have to spend 10 hours thinking about it and then taking actionable steps to implement it in order to make it useful. Teaching and writing are similar exercises that I have found helpful as a learning tool.
I only just stumbled upon why I like to read. It is likely very personal. But I have found that removing the distractions and habit of "horizontal reading" makes me happier. I'm looking forward to reading the referenced book by Birkerts.
(Aside: At times, I have found reading to be an excuse for not getting things done on my projects. _I just need to know more about x, y, and z before I start_. Ironically, the quest for knowledge can be distracting itself.)