I have many pet peeves and things that annoy me. One of them, in contemporary occultism, is the tendency of people to ask how effective a book is. Or perhaps saying that one book is more effective than another. That is like children saying that their bicycle is faster than another's. The speed of a bike is not in the bike, it is in your legs. The effectiveness of magic is not in the book, it is in your spirit. All books are equally effective (or not). Even made up shit is effective, the Necronomicon being the most famous example.
Now a ten-speed can go faster than a tricycle, but get a grip on where the power lies. There are times when a tricycle will outpace a Schwinn.