I have a lot to discuss about Castaneda's work, but I'm going to try to make this review first deal with the book at hand, Magical Passes: The Practical Wisdom of the Shamans of Ancient Mexico, which is (essentially) a manual for the Tensegrity exercises that Castaneda and his inner circle began teaching in 1993 (the same time that his last "substantial" book, The Art of Dreaming, came out). This basically presents several hundred "moves", with photos and detailed descriptions, with section introductions that serve to explain the purpose of the "magical passes" ... except that they don't. This is the most frustrating aspect of this book, almost nothing in it is put into an actual energetic context, a scant handful of the exercises have any sort of an explanation of why one might be doing it, and that is typically only in the form of "moving some X energy to Y spot", without a reason that you might be seeking to do this.
As Castaneda in his other books is always trying to figure out WHY stuff is being done, this is a huge clue that he didn't write the bulk of this book. Now, I do believe that the introductory bits for each section are based on his notes, yet these are very uneven, ranging from classic Castaneda to stuff that I can't believe got past an editor (Don Juan is at one point "quoted" as saying "friggin'"!). Frankly, much of what's in here has no specific purpose ... parts of it seem to be "instructions from the Ministry of Silly Walks", and other parts seem like somebody trying to take the instructions for Rocky Horror's Time Warp and making them "sacred motions". Oddly enough, the most "Castaneda-sounding" part is the introduction to the section dealing with "passes" for Recapitulation, a process that in the books is generally followed in what is essentially a box, not exactly the ideal situation for doing gymnastics!
Now, I will admit that I have not bothered to try these various motions, but I have done a good deal of "energy work" over the years, and one thing that is consistent from tradition to tradition is that one is usually given rather detailed instructions of what one is supposed to be doing with the energy, however in Magical Passes the closest you get to that is directions "to move like you're pulling something physical" or the like, no "why" just a whole lot of "what" which is (at best) described as "freeing up energy" or "shifting energy". As such, the book is a hugely boring read, with 450 pictures (a significant portion which look like step-by-step instructions for Steve Martin's "Funky Tut") and accompanying turn/pull/twist/swing/whatever directions.
As noted above, I doubt that Castaneda had very much to do with this book, as it was another that came out either right at the time of his death or posthumously. There are bits and pieces here which "sound like him", but these are rare flashes in otherwise drab prose, liberally sprinkled with bits that don't sound like him at all. Here is where I'm going to veer off into "speculation" and only deal with this book peripherally.
Now, I do believe that Castaneda had contact with authentic shamanic teachers, especially in the 60's and 70's, although it is hard to argue with those who insist that much of what he presents as Don Juan's teachings seem to come from various "old world" traditions (be they Western or Eastern). In any case, I think that Castaneda had gotten his "authentic teachings" in over the course of his "classic" first five books. At that point it seems like he disengaged from whatever teachers that he had been working with and returned to Los Angeles and set himself up as some sort of a "guru", pulling in the various women that were to suddenly appear in the later stories. There is a fascinating site out there called Sustained Action, which was set up by former students of Castaneda to "try to make sense" of the various twisty bits of myth-making surrounding his teaching, and much of what follows is drawn from the things that I found there.
It is my belief that Magical Passes is a book done by Florinda Donner-Grau, Taisha Abelar and possibly Carol Tiggs and others to "push" their Tensegrity exercises as Castaneda faded. As early as 1974, Florinda and Taisha were "a team", being featured in a martial arts magazine demonstrating assorted Karate moves. If anything, the exercises resemble something more like Tai Chi (but without any sense of actual chi!) than anything that I've ever seen a Shaman perform (although I have had teachers who have been very adamant that any "action" requires a physical component, but this can be as subtle as a little flick of a finger, and not an entire system of "dramatic" motions). Again, I highly recommend the Sustained Action site for some amazing research into chronologies, etc. for the women that Castaneda pulled in around him. Most of these figure prominently in his later books, although it appears that none where where they were supposed to have been in them. Castaneda seems to have had a strange paranoia about images and names, forbidding his inner circle to be photographed, and having them frequently legally changing their names (often with several using the same "legal address" to do so, which could then be conveniently abandoned). They also seemed to get married and divorced a lot ... and not just in a "L.A." sense, but having marriages come and go over a 3-week period.
One of the clues that this system was created by "the Witches" (as they were called) is that one whole section of these exercises were "specific" to each of Castaneda's women ... which is all well and good except that these are supposed to be ancient forms! I suppose that if one says that Taisha Abelar is the stalker, Florinda Donner-Grau is the dreamer, Carol Tiggs is the nagual woman, and The Blue Scout, is, well, a scout, then they're simply in the role of archetypes, but I suspect not.
Interestingly, all these women have disappeared. Of course, with all the name, spouse, and address changing they did, they might very well be out there somewhere "under the radar", but following Castaneda's death (April 27, 1998 though not publicly announced until June) they dropped out of sight, although still supposedly "directing" the Tensegrity programs of Castaneda's Cleargreeen organization. In 2003 the desiccated (and coyote-disturbed) bones of "The Blue Scout" were found in Death Valley, and some believe that all of Castaneda's women committed suicide in an effort to follow him (despite his dying a rather mundane, nasty, death from liver cancer instead of "burning from within" and "sneaking past The Eagle" as Don Juan and his party supposedly did). Of course, there had been books by Taisha Abelar (The Sorcerer's Crossing, among others) and Florinda Donner-Grau (the less-than-stellar Shabono), but nothing since Castaneda's death.
Anyway ... as anybody who had read this far no doubt suspects, I can't recommend Magical Passes unless you're getting it just to complete your Castaneda collection. I don't think it's really by him. I don't think that it has anything to do with Shamanic knowledge. I do know that it's got about 30 pages of worthwhile stuff, while the other 200 pages are just crap. If you do feel a need of adding this to your library, it's still in print in paperback, but you could pick up a "like new" hardcover for under five bucks via the Amazon new/used vendors. Again, this ain't gonna add much to anybody's knowledge about anything, but sometimes you just gotta have it on the shelf.