What do you think of that Gerald Gardner guy?
Gardner was important in the grand scheme of the return of paganism as a viable religious construct, but he liked to make stuff up as he went along.
Who doesn't? As long as you don't butcher ideas or reduce them to a meaningless popcorn fluff tasting faintly of plastic...

Problems only arise once you start to sell your ideas as dogma, and pretend that they're 10,000 years old at the VERY least.
Having done an in-depth study of a couple of his books, and studied a bit about the man himself at one time, allow me to lend some insight.
Though Gardner was very intelligent, he was more self-educated than formally educated. As such, he was very knowledgeable and talented, but doubtlessly had significant "gaps" in his education. He was dedicated and meticulous in his research, but suffered from two personal flaws which significantly affected the quality of his work (especially where Wicca was concerned); he tended to form conclusions before or during his research, and his love of attention encouraged him to present verifiable information as more 'sensational' than was warranted.
Some have said that he was less than attentive in establishing the credibility of his sources, but I believe this was an extension of his problem of pre-conceived conclusions, i.e., if the source in question agreed with his work, it was credible; if it didn't, it needed further research. Also, it has been noted that. in many instances, he would "fill in the gaps" where research came up short. Gardner felt that if anyone were to propose additions to such gaps, that it should be the person with the most extensive knowledge and experience that could be found. So naturally, he volunteered himself.

In a sense, he had a point, but had completely sacrificed objectivity.
One good example of his flawed research would be the Clavis Salomonis, or Key of Solomon, which Gardner used to establish many of the ceremonial practices of Wicca. This document was presented as a guide for ceremonial magic, written by King Solomon himself. I believe that Gardner had an idea that this document was likely a forgery (since he had at least three different translations of it in his library) but never divulged that information. Nonetheless, this document *can* be traced back to the 1400's, and as well, appears to be influenced by the Jewish Kabbalah, which potentially brings overall antiquity to as early as the 2nd century. So while he may have
felt justified in accepting this as an "ancient" source, he was "short-cutting" the proper process of research.
Overall, I still believe his books are a good source of information, though all of it needs to be read with a very critical eye.
Literally,
-- Druweid