A fun, juicy, gossipy, and insider-y read. Certainly falls short of the Five Star "Amazing" standard, but I don't think the author was even aiming for that territory.
The book can really be split into two sections, parts which are wildly different in tone and content.
The first half is reasonably sober, somewhat detailed, theoretically well-researched and straightforward chronological telling of the first several decades of the Metropolitan Opera. There is a lot to be learned, and probably the most important is the early stages of THE enduring theme in the life of the Met and source of much of the spice and sizzle that dominates the second half: The Met as Magnet - and Vacuum -- of Money and Conferrer of Social Status.
The second half is where things gets much less serious and where all sense of writerly discipline and historical responsibility fall apart. The second half casually rejects the chronological approach, allowing the author to settle old scores (sorry, couldn't resist) and dish dirt in a serial way about... Rudolph Bing, Anthony Bliss, James Levine, Luciano Pavarotti, Placido Domingo, and -- with the most relish -- the hellish little diva, Kathleen Battle. Here we jump forward and backwards through the years and some details are told repeatedly with no nod to the fact they have been shared or cited before. This feels like -- ok, this IS -- sloppy writing and even sloppier editing.
Fiedler is not above -- ok, VERY not above -- making cheap and underhanded nods to irresponsible and salacious rumors that are beyond UN-subtle. After about the, oh, fifth or sixth reference to how much James Levine "guards his privacy," how "rumors have circulated" about his private behavior, how etc etc etc. OK, OK we GET it. Move ON.
What Fiedler ignores throughout the book is the fact she worked at the Met for years. We do not get any discussion of how and why she left the Met...or what she actually did while there. This is noted in the author blurb, but the absence of forthright honesty about this point in the text adds to the sense she out to exact revenge and payback. And for a woman who knowingly talks about the egos of famous musicians and in particular of conductors, Fiedler never mentions once her father... Arthur Fiedler, the iconically white haired, fire truck riding conductor of the Boston Pops.
So, ultimately, if you are into opera, read this book. You will get a ton of gossip and dished dirt. Take the dirt with a grain of salt and move on.