I was having a discussion with a (currently serving) elder recently when he brought up a straw-man argument that went something like this:
Elder: I've been invited to speak with other Christian groups, you know what they do when studying the bible?
Me: No, I'm not sure, what do they do?
Elder: They read a verse or chapter, then go around the room asking how everyone interprets the reading. And you know, every one of them give a different answer on what they believe it means. Jehovah's Witnesses don't do that, we all share a common understanding of what it means because the faithful and discrete slave has given us the meaning.
Me: I think many JWs have their own beliefs/doubts but won't mention them because they're too scared of being disfellowshipped. And any who do disagree are quickly routed out of the congregation.
Elder: * Silence * .... Change of topic .... Made excuse to leave