To recap, what I originally said here was:
I don't think it is true that both parties necessarily wind up with more accurate estimates after updating and agreeing, or even an estimate closer to what they would have obtained by sharing all their data.
The scenario in the grandparent provides an example of an individual's estimate becoming worse after Aumann agreeing - and also an example of their estimate getting further away from what they would have believed if both parties had shared all their evidence.
I am unable to see where we have any disagreement. If you think we disagree, perhaps this will help you to pinpoint where.
Perhaps I was reading an implication into your comment that you didn't intend, but I took it that you were saying that Aumann's Agreement Theorem leads to agreement between the parties, but not necessarily as a result of their each attempting to revise their estimates to what is most likely given the data they have..
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