Pfren, that doesn't really answer the question.
I'll grant that a person who reads books will likely be a better player than one who does not.
My question is not if a trainer is sufficient for maximum improvement. My question is if a trainer alone can be sufficient to get a player to the NM level.
I find it hard to believe that is not possible. I will grant even that it might take a very good trainer. But I find it hard to believe that if we could get Yusupov and Dvoretsky to work with a promising scholastic player every day for 3 or 4 hours for many years that they would be unable to get that person to 2200 or so without having the student read a book.
Ultimately, though, I do believe it is entirely a theoretical question. In reality a good trainer would want a student to read particular books. And a good student with real talent would want to read particular books. And of course, very few people would be in a position to hire that quality of a trainer for daily work in the first place.
I believe Scotts statement is a true one in a theoretical sense, whereas Pfren is correct in a pragmatic and realistic sense and under the current state of technology. In our current socio technological environment, a lot is still dissipated optimally in the format of books, both traditional and e-books. In theory a teacher could read those books to his student, but this misses the point a bit and would be economically to expensive.
A long thread to say that we love you both and that we enjoy the conversation utterly :-)