Is Christopher Penczak a credible Wiccan author?

I have two of Mr. Penczak's books in my library and in all honesty I do not reach for them as often as many other authors. I can not speak to his crediblity, however they are not as pertinent as others.

The books came to me when a member of my Circle passed them on after reading them. His choice was not to keep them, but thought it would be helpful to have them in the library in case someone else referenced them.