Thanks for all the comments. There have been too many great comments whilst I was sleeping to refer to all of you. A couple worth mentioning.
James_woods - We had a thread a couple of days ago - "Do JWs still believe in 1914"?
That thread is what got me thinking about this topic. The ignorant apologist responses shocked me, how can intelligent comments on a subject be so easily dismissed, glossed over or misunderstood?
Prodigal Son - that is an amazing letter from Bethel. The whole subject of disfellowshipping seems to be back to front.
Fatboyslim - I think that Watchtower doctrine has always been simple, but as you point out, it was wrapped up in very complex argumentation that JWs actually bothered to learn and recite. But peal off Franz's flowery rhetoric and the core teachings were basic, black and white doctrine that did not cater for the nuances of the Bible. They have always been a religion that used eisegisis as much as exegesic to form their arguments. Now they don't bother to try to justify the doctrine.
The latest study books state doctrine with absolute minimum of reasoning to support it. There are so many comments to trust the Governing Body, that the followers that remain, or join these days, accept anything stated in the Watchtower at face value.