First, you are applying the "rules" of the academy of 2006 to 150 AD. It was accepted practice to write in the name of another person - it didn't automatically condemn the writing. Very few people believe that Peter actually wrote 2 Peter, and many scholars disagree that Paul wrote the Pastorals. This doesn't change the view that scholars have that these writings reflect the view and philosophy of Peter and Paul.
While I agree that the document has questionable material in it, that doesn't make the entire document false. And as I have labored to say, Marian doctrines don't originate with this document, so it is really a moot point to argue the document's historical value. Can anyone doubt that Mary's mother is correctly listed in the Gospel of James? My theory is that there was oral traditions floating around (just as there were BEFORE the Gospels were written) and the writer used the known ones, adding in legendary accounts to fill in the blanks. Thus, I would venture to bet that a lot of the background information is true - while the narratives and stories are of a different literary genre that "CNN reporting".
Regards
"While I agree that the document has questionable material in it, that doesn't make the entire document false."
Following this defense I suppose we should look at the Gnostic books as legitimate.
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"My theory is that there was oral traditions floating around (just as there were BEFORE the Gospels were written) and the writer used the known ones, adding in legendary accounts to fill in the blanks."
This is why those of us that are not RC refuse to consider "Tradition" as a reliable source. It can be added to or deleted from at will to fit the times. It's a shame that we don't have any reliable sources of information about Mary. She was obviously a very special woman and I think there were parts of her life that would have been inspiring to know about.