I haven't read the book, so probably shouldn't comment. I was trying to make fun of the people that believed that nonsense by saying it was like believing in National Treasure. I guess I had only caught part of an interview on TV, because that was all I remembered, was the author saying it was a work of fiction.
He seems to believe the underlying point is true - the diety of Christ is based on fraud, the Church repressed the female goddess religion, etc.
And in the beginning of the book he has a fact page, with a couple of whoppers:
Fact:Thanks for your reply.
The Priory of Siona European secret society founded in 1099is a real organization. In 1975, Paris's Bibliothèque Nationale discovered parchments known as Les Dossiers Secrets, identifying numerous members of the Priory of Sion, including Sir Isaac Newton, Botticelli, Victor Hugo, and Leonardo da Vinci. [this is an admitted fraud]
All descriptions of artwork, architecture, documents, and secret rituals in this novel are accurate.[Hornswaggle]