While he is not a practitioner we owe a lot to Peterson.
Most people now don’t realize that for the 20th century all this magic stuff was considered trash, least in the English speaking world. It was almost impossible almost to find any good primary texts, and everyone was working from very sparse source material. I had Idries Shah's 1957 book The Secret Lore of Magic that a stranger gave me at a party, Waite, and Crowley's rippoff of Mathers to work from, and I made it work.
Then Peterson comes out with the Lesser Key in 2001, the Grimorium Verum, Heptameron, Arbatel, all straight from the best manuscripts, footnotes, corrected names, the works. And if I recall, The Fourth Book, Sworn Book, 6 & 7 Books of Moses , all hitting between 2000 and 2010 or 2011, every one sourced from the old manuscripts from libraries around the world, footnotes, parallel Latin/English, the whole deal.
Look at just the massive influence of just one book alone, Reginald Scott's The Discoverie of Witchcraft , which people used as a grimiore. Even the British Cunning Men and Women had to collect scraps. Peterson is a one man Cambrian explosion of manuscripts. They were all put to good use by magicians.
