Lee:
I'm inclined to mostly disagree with your review of "History of the Occult Tarot." I didn't find the authors' tone "unfailingly disapproving," nor did I note any tendency on their part to "lash out with satirical and ironic remarks." The portraits they offer of, for example, Manly Hall, Eden Gray, and Gareth Knight are respectful and sympathetic.
For example, in describing Gray's tarot reading technique, the authors contend that "...she was able to intuit the seeker's image of himself and thus predict events likely to proceed from that self-concept. At the same time, she recognized her great responsibility. If the seeker is susceptible to suggestion, he may accept a cartomancer's prediction, and subconsciously strive to cause its fulfillment." (p. 299)
Decker and Dummett call Gareth Knight "...a very relaxed exponent of the esoteric Tarot. 'The Treasure House of Images' contains an accurate history of the Tarot pack; Knight considers it important for occultists to know the true history of Tarot, and to be familiar with different early versions of the trumps." (p. 281)
Furthermore, even when discussing the significant work of people and groups with whom they disagree, the authors seem willing to give credit where it's due. In summarizing the work of the Golden Dawn, they say, "The Golden Dawn gradually elaborated a detailed and coherent system of magical theory and practice...In the course of elaborating these instructions, the Golden Dawn achieved a definitive summa of magical theory; that was its lasting accomplishment." (p. 96)
Your characterization of the book as an unrestrained attack on occultism and occultic approaches to Tarot might more aptly apply to their earlier work, "A Wicked Pack..." That book's stated objective was to dissipate, once and for all, the spell of foundationless speculation and the thick mist of ahistorical assertion under which Tarot history had labored for 200 years, and it succeeded. "A Wicked Pack..." did indeed adopt a thoroughgoing tone of (justified) sarcasm, and in it Decker, DePaulis, and Dummett stopped just short of accusing Eliphas Levi of fraud, and in Paul Christian's case did not bother to stop short, asserting that "(Christian) continued, as we shall see, to act on the assumption that to readers of books on the occult one might lie without disturbance to one's conscience." (p. 195)
True, some of the personalities dealt with in the new volume end up looking ridiculous. However, I think this is more their doing than the result of any attempt by Decker and Dummett to make them look bad. It would be difficult to read even a sympathetic account of the lives of S.L. Mathers and Aleister Crowley without coming to the inescapable conclusion that both were walking examples of the severest extremity of narcissistic personality disorder. It's also old news that Builders of the Adytum has for years avoided the subject of Paul Foster Case's personal life.
On the whole I didn't find this book as satisfying as the earlier one. It had little of the excitement and electricity that characterized the ground-breaking work of "A Wicked Pack...," and once the chapters dealing with the Golden Dawn were finished, "History of the Occult Tarot" degenerates into a rather weary recitation of personal histories interspersed with tables of cabalistic and astrological correspondences. Much of the weariness, I suppose, can be ascribed to the fact that most of these latter-day systems ultimately derived from the work of Levi, and the subsequent systematization and program of practical application which the Golden Dawn created out of Levi's rather disorganized body of ideas. Altogether, it shows the futility of attempting to construct an architecture of rigid correspondences involving disparate esoteric systems.
As for your complaint that the authors did not offer a counter-interpretation of the meanings of the trumps and the trump system, this was not their objective; the titles are "Origins..." and "History of the Occult Tarot." There is, however, a brief theoretical exposition of the meanings of the trumps on pages 44-47 of "A Wicked Pack..."