I recently had a conversation with an ultra-PIMI relative regarding the overlapping generation. Despite all his pioneering, personal study, and assembly parts, he had no idea about it. He had to latter come back to me and apologise that I was correct. What amazed me about this incident, was for such an important aspect of which the faith hangs on, he was totally clueless. Needless to say he is still pioneering and to be honest wt can have him.
Talking about the Christadelphians. When I first left the JWs, I actually attended a couple of christadelphian services. Mainly out of curiosity. I was shocked to find that I could use JW terminology and doctrine and they knew exactly what I was talking about. Another religion worth investigating is the Iglasea ni Christo - I’ve also attended there as well.