” And unfortunately good, valuable marking of books really is a ‘trade secret’”
Did you work for the FBI?
Lol. I do appreciate your cordially non agressive tone.
At the core is knowledge, what is knowledge, how is it composed. There are Masters Degrees on this subject.
Highlight readers are superior to non highlight readers.
So I am not demeaning highlighters. Just ask a person to summarize a book they recently read, someone who does NOT mark on books.
The non marking reader retains less, AND most important is that for them to go back and review, they must reread the book again.
Readers are smarter than non readers.
Highlighters retain much more than readers.
Then Trade Secrets, a publishing editor may have some.
All books are the original outline, covered with fluff. Reading is recovering the original outline.
By understanding that principle, one can 4.0 GPA any college course.