I agree Terry.
What was new for me in your post was the explicit linking of the creation of the GB to the failure of the 75 prophecy, which is a genuinely interesting point. I don't remember Ray Franz really mentioning many details of the GBs emergence in CoC, only that Freddy Franz was vehemently opposed and he railed against it in the gilead graduation class talk of 75 (I think) etc. Maybe I'm forgetting something obvious though...
I guess regardless the GB was a reaction against the Presidency (Knorr and Franz), however you look at it.