I have had the pleasure to meet Jim Penton. He was raised in the JWs (3rd generation, if I remember correctly) and was able to achieve an education to the level of PhD in religious studies while still a JW.
He even wrote a book that praised the JWs "championing" of civil liberties in Canada. He claimed to be an "anointed" JW, meaning that he believed that he would be one of the 144,000 who would rule in heaven with Jesus during his 1000 year reign over the earthly paradise inhabited by JWs.
He was disfellowshipped in the late 70s/early 80s for coming to the conclusion (from his own Biblical research) that JWs are not required to go door-to-door. Apparently his being Anointed™ by holy spirit still wasn't an adequate credential which would allow the scriptures to speak to him directly, instead of requiring the interpretation of the Faithful and Discreet Slave™. My guess is that he felt that his perception as being Anointed™, coupled with his advanced education in religious studies, made him feel that he had every right to examine the Bible the way he did, just as much right as those Brothers™ who comprise the Faithful and Discreet Slave Class™.
Since then he has written Apocalypse Delayed (first edition circa 1980) which is a critique of the WTS and its doctrines and practices, making him Canada's first Apostate™ of renown.