I heard Morlan speak about ten years ago at my local KH. He packed the house. People came from neighboring congregations just to hear this talk he was known for giving on Revelation. It was just about the most urgent, convincing, and exciting "last days of the last days" talk I ever heard. Everyone hung on his every word, and he seemed so convicted of his material he could barely contain his own excitement. He really knew his stuff, could explain JW end times doctrine backwards and forwards and really sell it.
In light of this James Jack's story is very interesting indeed. I think some longtime DO's who are both heavily invested and knowledgable are among the most likely to have deconstructed the GB's doctrines over the years. Whether or not they can see that it's all BS I think depends more on their emotional state than on any lack of intellectual capability.