I hadn't thoroughly looked at Incesticide and while it's still lower on the list of my fav Nirvana albums, this book helped me appreciate it more. Much of the book, however, is a fairly dry cataloguing of facts about the band and Cobain's songwriting. These parts didn't do too much for me, although Soulsby's data mining is admirable. The parts I enjoyed had more to do with Soulsby's subjective analysis of the songs, their meanings and themes. This might not have thrilled Cobain, who often insisted that his lyrics were meaningless collages of words and nothing more. And he hated to talk about meaning, but that is a trait many artists share, so not surprising.
But whether Cobain would admit it or not, many of these songs carried meaning and interesting recurring themes. The sarcastic mocking of media (and fandom), the nature/body amalgamation, biological and familial fatalism, the strong inward focus and the conflicted desire for annihilation, all there. Nirvana was a particularly apt name for this band: "freedom from pain and suffering in the external world"... indeed, most of these songs (post 1990 at least) had a remarkable lack of focus on the external world; these were primarily inward, inner, introspective songs, Soulsby rightly points out.