I'm enjoying the book, first couple of chapters give an interesting history and context of the growth of "prog rock" out of psychedlia and an examination of what it actually is, inclduing the "crossover" with classical. He then gets into diferent bands, starting off with KIng Crimson and I don't think many wlould dispute that their debut was the first prog rock album. There's some interesting snippets from interviews with various band members and its offered a great insight for me (some of you may be more familiar with the story). It's led me to listen or re listen to some of the King Crimson stuff I hadn't heard before.
I've also read chapter on the first part of PInk Floyd's careeer (up to and including Dark Side of the Moon). Although I'm much more familiar with their story there are still new insights from interviews with those who were there at the time.
I thought I might lose interest when getting into discssions about bands I don't really follow, this might still happen but curently reading about ELP and rather than lose interest it has made me want to give them a listen.
I suspect that the authors very technical descriptions of some of the music might get repetetive but up to now I'd have to say I'm very glad I bought this book, well worth a read.