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For those who are familiar with the various contours of the Hockey Stick debate over the past nine years, there is only one thing that needs to be said in this review: the name 'Montford' does not appear anywhere in Mann's book - not in the main body, not in the footnotes, and not in the index. For those who haven't a clue what I am talking about, I am referring to the book by Andrew Montford, "The Hockey Stick Illusion" (HSI). Montford's work presents the alternative perspective on the so-called Hockey Stick War, a work that came out in the wake of Climategate 1. He carefully and extensively documents all of the minutiae of the hockey stick debate, including detailed, but fully readable, explanations of the controversial scientific and statistical points, the twists and turns of the publishing and peer review processes, the outcomes of the congressional hearings, the manipulations of the IPCC process, and the discoveries of undisclosed problems with successive "hockey stick" studies. Overall, the book is a damning indictment of Mann's scientific method and his maneuvers to try to cover over his errors. For Mann to completely omit any mention of this book is a telling admission that he does not want his readers to hear "the other side" of the story. This omission is a characteristic of the book as a whole. Rather than responding in a meaningful way to the significant and documented criticisms that have been raised by many, he fills his book with a lot of bluster, hand-waving, and accusations that his opponents are simply 'corporate/industry/fossil fuel/-funded, well-organized deniers, who have been thoroughly discredited.' Of course, he provides scant evidence to substantiate these accusations, particularly with respect to his most prominent detractor, Steve McIntyre. But the rhetorical effect is very powerful, and it no doubt persuades many (as evidenced by the number of 5 star reviews here). One hears repeatedly that Mann's work was vindicated by the NAS study - a point that Mann relies upon in his book. However, those who have actually read the NAS study, and those who have actually read or listened to the House Energy and Commerce Committee hearings realize that Mann's methods were thoroughly repudiated by both Wegman AND the NAS panel. Under sworn testimony, Gerald North, chair of the NAS panel, was asked if he disputed the conclusions or the methodology of the Wegman's report. He responded, "No, we don't. We don't disagree with their criticism. In fact, pretty much the same thing is said in our report." Yet, Mann is somehow able to conclude that "In the end, the conventional wisdom was that Barton and gang fared poorly in the two days of hearings that summer" (Locations 3461-3462). This statement can only be supported if you assume that Mann is the sole possessor of "conventional wisdom." There have been two primary criticisms (and dozens of secondary ones) leveled against Mann's hockey stick reconstruction: questionable statistical methods, e.g. incorrect PC analysis and poor validation statistics; and the reliability of tree rings as temperature proxies (bristlecones and foxtails in particular). However, Mann completely omits discussion of any criticisms of tree rings as a temperature proxy until he begins discussion of his 2008 paper. This in spite of the fact that he had just finished discussing the Loehle 2007 paper, which was explicitly conducted with a view to create a millennial scale temperature reconstruction without using tree rings. Nevertheless, he is constrained to begrudgingly address these criticisms because his 2008 paper was written ostensibly to demonstrate that the hockey stick is preserved without the use of tree rings. Nevertheless, amongst the many problems with this study (e.g., the use of upside-down contaminated sediment records, data infilling, truncated divergent series), the most striking was that the reconstruction only yielded a hockey stick if either bristlecones were included OR the contaminated, upside-down Tiljander sediment record was included. Take both of these out, and the hockey stick disappears! Mann 'forgets' to mention this part of the story, even though he eventually admits this in the Supplementary Information to the paper. Mann's discussion of the Yamal tree ring record of Briffa is equally intriguing. This proxy series from the northern Russian peninsula of the same name was one of the dominant hockey stick-shaped series used in multiple temperature reconstructions. The raw data for this series had been withheld by Briffa until late in 2009, when he was forced by the journal Phil Trans B to archive his data (after 9 years). With the release of this data, McIntyre quickly realized that the sharp upward trend of the late 20th C was the result of a mere 10 cores in 1990, dropping to 5 in 1995. Moreover, amongst that paltry few, a single tree (YAD06) with an 8 sigma 20th C deviation was shown to be almost solely responsible for the Yamal hockey stick shape. Of course, Mann neglects to share this tidbit of information in his discussion of Yamal. However, he does make a most remarkable statement, claiming that "Most climate reconstructions either didn't use the Yamal series in question anyway", for which he adds the end note: "This includes the hockey stick itself" (Kindle Locations 3944-3945). This is a starkly disingenuous comment. Both MBH98 and MBH99 pre-date the publishing of Yamal in Briffa 2000 and thus it was unavailable to the hockey stick. More than that, Yamal appears in no less than 10 of the so-called "independent" reconstructions that supposedly "confirm" the hockey stick, of which 5 are included in the IPCC AR4 Spaghetti graph (Mann's Figure 12.1). Most egregious, though, is that Mann himself uses Yamal in Mann and Jones 2003, Mann et al (EOS 2003) and Jones & Mann 2004. Hardly insignificant. There are many more problems with Mann's work, which can't possibly be fully explored here. His discussion of Climategate deserves many pages of comment for the ways that he sidesteps the most troubling aspects of the whole affair. There are stories of imaginary spreadsheets, incorrect use of statistical terminology (i.e., "censored"), self-contradiction, allegations of criminal misconduct, manipulation of IPCC reviews, the Wahl & Ammann study and much more. So if you are interested in the history of the hockey stick, do yourself a favor. By all means read Mann's story. But read the "Hockey Stick Illusion" as a companion book - and then you decide which account is more credible.