In response the question Mankkeli asked me, I think the GB were indoctrinated by their predecessors and their publications. That's not to say that they don't add their own ideas to the mix. Ray Franz indicated in CoC that the GB members think of the organization as if it is some sort of entity different from themselves, something greater than just a corporation that they run themselves. He considered them to be captives of the "faithful and discreet slave organization" concept, seeing themselves as leaders chosen by Jehovah. If that's true, it would be like the man behind the curtain forgetting that he was just a man manipulating levers and truly believing that he was the wonderful Wizard of Oz.
If Ray is right, then the GB doesn't realize its overlapping generations teaching is a scam. They really believe Armageddon must come within the 1914 generation and the overlapping generations doctrine "must" be the answer. In other words, they believe it themselves. I don't know that for a fact, of course.
From what I've read, I think Russell really came to believe that he was God's Laodicean messenger. It also seems that Fred Franz believed his own created doctrines, especially the importance of 1975. Rutherford seems more like a person who understood that he was making stuff up as he went along, but even he may have believed his own writings. Hard to tell.
