This has been a wonderful post to follow. I grew up in SC and lived in Charleston for many years, and I hadn't even heard of Jim Callahan until reading this post. However, I knew of Criss Angel and was amazed to see that the credit for the Youtube video where he, Uri Geller and Jim Callahan have their heated moment, was actually posted there by jimclass(dot)com.
Still reading through the thread, there's alot of amazing conversational misdirection technique, back talk and ad hominem argumentation going on (not like that's not seen here, but unexpected and bizzare just like the OP said - especially in reference to that forum)
On a side note, what Jim does is something alot of SC kids learned to do growing up - myself included, and that is faking possession. When we got bored with church, revivals and especially if we didn't like the preacher, it was a fun thing to do.