That this book is very well written is, of course, important for readers. But the terrific job Montford does in explaining the whole hockey stick graph controversy is the greatest value of this book.
I learned many things of which I had been unaware in my layman's ignorance of the actual functioning of science journals and the way that world functions. For instance, we hear the phrase "peer review" trotted out as though any paper that has undergone "peer review" and deemed worthy is unquestionably true. However, Montford shows that Mann's two hockey stick papers underwent peer review and were approved. But when McIntyre asked to see the actual data and data processing code that went into them it became clear that no one had ever asked for them. The editor of one journal in the climate science field replies irritably to another McIntyre request for the data behind a paper that no one has ever asked for that before.
Inevitably, one starts to wonder of just what these supposedly thorough peer reviews consisted if no one had ever asked for and check the actual data on which anyone's paper was based.
In a lucid style, Montford explains fairly arcane statistical and physical science issues making the details of the controversy comprehensible. You find yourself rooting strongly for McIntyre and McKitrick, the incredibly persistent little guys fighting the snobbish and to varying degrees corrupt gate keepers in the climate science field.