My Theory: RITE — Ritual Instrument of Textual Esoterica

[LisaFaginDavis]

"This can't possibly be the only thing that person ever produced. (Well, anything is possible. I suppose every other sample of their hand might have been destroyed... fires etc.)"

Only about 5% of manuscripts produced in the Middle Ages/Renaissance survive. It is not at all surprising that there haven't been more examples of Voynichese found - even if they once existed, the odds are always against survival of any particular manuscript. 

As for it being the forgery, for me the issue isn't the cost, but the actual material evidence. The provenance evidence, the binding evidence, the annotations, the different styles of additions and annotations, the effaced inscriptions, etc., all speak to its authenticity. I'll be speaking about these issues in my lecture on 9/26.

It might be gibberish and nonsense, but that's different from "forgery." The word "forgery" implies a modern object presented as an authentic ancient object, which is a completely different question from whether the manuscript has semantic meaning. It's of course possible that someone in the fifteenth century created the manuscript to trick someone into buying it, but that doesn't make it a "forgery."