The only way I know how to describe this book is "brain food." It changed the way I will view literature in the future. It had a lot of interesting analytical insight without turning analysis of literature into nothing but a mathematical equation. Although there was some geometry involved.
There was a whole segment on perspective and since the author was comparing writing to map making he included an "upside down" map of the world created by New Zealand mapmakers that totally fascinated me. Take a close look here and see if it does not shift your world viewpoint a little bit.
Another highlight for me was an explanation of the methods Edgar Allen Poe claims to have used to create "The Raven."
Low lights would be when the geometry got a little intense and complicated.
This book also was a bit of a vocabulary lesson for me.
Scylla & Charybdis: sea monsters from Greek Mythology.
Elision: the omission of a vowel, consonant, or syllable in pronunciation
Aphorist: An aphorism is an original thought, spoken or written in a concise and memorable form
Cacophony: unpleasantness of certain sounds of words or sentences
Bildungsroman: coming of age story
Verisimilitude: appears to be true