I am just starting to get into the sport a little more (personal maintenance/repairs, history, training) and this book was a great read. I enjoyed it mostly for it's interviews and opinions of the participants directly involved in the event. There is a good amount of history covered in the first 2/3's of the book (author mentions this in the preface) but it's completely necessary and does a great job of framing all that ends up happening around the 1986 tour.
I didn't know much about this topic before reading this book so there is a possibility that if you were alive during the tour and or an avid cycling fan you might already know a great deal of the information presented. In addition, even though I knew LeMond won this tour (spoiler alert?) I didn't know how each stage played out (minus L'Alpe d'Huez) so reading about each stage was very engrossing and held my attention very well.
The only addition I would like to see is more history about the participants after the 1986 tour. Moore comments on this a little bit but not as in depth as the history before the tour. It'd be interesting to really see how this particular tour shaped not only the individuals but ultimately the sport.