The Modern Forgery Hypothesis

[asteckley]

In fact, the ENTIRE evidence for the provenance of the VMS between ~1438 and 1912 hinges on that letter describing the book B and no other book.

Well, no. The first evidence is the C14 dating, coupled  ... the hypothesis of it being a XXth century forgery requires a lot of improbabilities to be overcome, that's the harsh reality.

Yes, yes, we all know there is the whole set of evidence that is consistent with the genuine 15th century theory. No one has said there isn't. None of that changes what I said (and which you quoted).  

If the hypothetical book described by Baresch were to be found today, then all of the provenance that we have for the VMS between ~1438 and 1912 simply collapses. That alone shows that everything about the provenance (actually just prior to 1912, since the C-14 does not prove when the book was written) hinges on the described book being the VMS and only the VMS.

And finding such a book wouldn't prove the modern forgery theory -- and no one has claimed that either. It would only negate one of the most common arguments used to say the VMS definitely existed by the 17th century.