Like many spiritual books, this has clearly been published with very little editorial oversight and struggles to consistently focus on a single topic in a sustained way. Add to this that the more interesting ideas are constantly mentioned as being in another book (which is the only text actually referenced within here — no bibliography makes me highly suspicious of pretty much everything mentioned within!!) makes this text actually seem highly reliant on a very specific set of spiritual practices. The use of Kabbalistic terms in such a decontextualised way makes me very suspicious, and I have some concerns about the preoccupation with the concept of purity, particularly when the author describes certain people (such as Indians) as being 'spiritually dirty'. This is a very clear ethical concern with the tone taken in this text.
This is not to mention how McCarthy continually contradicts herself with respect to her attitude to morals. On the one hand she claims that all bodies are different and it's not a moral question, but then proceeds to spent full chapters discussing how grains are spiritually impure and goes on to moralise about how genetically modified foods are going to kill us all. But McCarthy also endorses homeopathy by endowing it with far more respectability that its own history deserves. This is to say that she relies upon a kind of folk spiritualism that speaks down to what it doesn't understand.
Generally the tone taken in this text indicates that McCarthy feels the need to continually assert her own authority and experience without ever explaining this experience and continually talking down to the reader. But, given the lack of detail, it is very difficult to take her seriously as a teacher of any kind. Perhaps her other work is better, but I am unlikely to make time to read it given the quality of this.
If you want to use tarot to try and diagnose your physical ailments then perhaps this will be useful for you. But otherwise, this book is only really useful for hearing McCarthy's thoughts on things she does not seem interested in explaining. But, as she continually reminds us, she such an experienced magician. One might have thought that some of this experience would have been able to produce a better book.