Without the internet and sites like Goodreads you'd never hear of books like this. So thank you it's been a most enjoyable read.
There isn't much by way of clinical insight; Crouch identifies the elements of a good novel in the same way as a non-writing English teacher identifies them. He comments on structure and characterisation and the other building blocks. Once that is out of the way he is able to demonstrate that his purpose in reading the books is not to be an expert (he is by dint of reading far more than most) or in being a critic. He reads them because he loves children's literature and this love shines through. You rarely think, "My word, what a penetrating insight." You often think, "Yeah, I thought that as well".