Without a doubt, the three founders of the original Golden Dawn- Mathers, Westcott and Woodman ( not to be confused with some groups claiming the name today) were influenced by the magical writings of Agrippa. What magician in the past 500 years wasn't? I cannot think of a magical concept that is missing from the 900 plus pages. Agrippa wrote this book in the latter part of 1509-1510, and for all those who have the book The Magus, by Francis Barrett, you can see right away where Barrett got his materials. Straight from Agrippa.
This is a reference book that everyone should have, although there are some differences to be found between Agrippa's work and that of the traditional Golden Dawn. I think this book is useful to all magicians - but a lot of the material is not for the beginning practitioner. For those who live and breathe the Golden Dawn and other systems of western magic, the information on the Cabalie (Qaballah), the numbers, the elements, and the Sephiroth is invaluable. The writings concerning spirits, emanations, angels and Divine beings are very interesting and informative. I could go on for pages and pages. Agrippa is Agrippa and this classical work has influenced occultists for centuries.
I do not agree with many of the editorial comments added by Tyson, but then I don't agree with many of the things that I have seen him write involving magic. Inspite of the comments, this book is a MUST have for anyone who is interested in the history of magic, magical practices or hermetics whether they study classic Golden Dawn or not.