'An ad for a product no longer available'

In this passage, written in 1982, Brian Hill discusses Energy Unbound: The Story of Wennington School, by the school's former headmaster, Kenneth C. Barnes.

KENNETH'S book is, as a matter of fact, irrelevant — that's possibly the most appalling thing about it, for him, for Wenningtonians, for anyone involved. Alas, as I may have said before, it's advertising copy for a product no longer available. It isn't a "history of the school" or a real account of even part of it. His remarks on dancing and dances (to choose an innocuous example) are just not true, not faithful to fact, emotion or experience: there were dances with marvellous atmosphere after he left, and while, before that, he sulked elsewhere. At no point in the book, so far as I recall (I don't look at it often) does he really show personal understanding, gratitude, criticism, or real thought, about any member of staff: they're all made anonymous so that KCB can dominate. Of course, it would have been very difficult to do anything else - but the fact that that is so makes the book irrelevant. He isn't Bertrand Russell or an autobiographer of integrity. Schoolmasters exaggerate schools, anyway: the lives of their pupils mainly consist of things they don't know anything about. Hence their reports are usually wildly irrelevant to suffering or triumphant children - if they practise alleged psychology, all the more so.

I think it possible that only poets, novelists, artists, musicians get anywhere near what it is like to be a living human being, and they don't (or shouldn't) dogmatically apply theories and try to classify. (I dread to contemplate the lies that were said about me to my knowledge, and what I don't know about must be horrific - all uttered by "Christian persons" thinking they were acting responsibly!)