The title of this book makes it sound far more mystical and questionable than it actually is. Truth be told, I side-eyed the title but was pleasantly surprised by its contents once I cracked it open.
It's not only well sourced, using the primary sources for Ogham, but it's also clearly cited where otherwise deviating from that primary material. And it has footnotes and a bibliography- rare sights, both, when it comes to Pagan books, and incredibly refreshing to see. The author also does a wonderful job labeling where something is a personal addition, interpretation, or practice.
Speaking of, the book is more research and explanation than it is a personal guide through Ogham's modern mystical uses; I found it mostly useless in examining someone else's practice with them- but found it to be a great guide through the Scholar's Primer and the Ogham tracks, and incredibly helpful in understanding them.
My only complaint was that he makes one mention of the color White being "the traditional color for divining". This claim wasn't sourced in the book, nor could I corroborate through academic texts when I went looking. That's the only thing that pinged my
"sources please"
radar, however- which is a bloody miracle in the Pagan world. That being said, my knowledge of Ogham is low, and so it's very possible I'm not knowledgeable enough to have caught any other problems.
Knowing what I currently know, however, I'd say this is definitely a good book to pick up if you're interested in Ogham.