Why I think that the copyist(s)/scribe(s) did not fully understand the material

[Koen G]

If we're looking for things that changed in Europe after 1450, I'd place book culture on top of that list.

I agree that there are certain human universals. But "the need to keep handwritten secrets" does not feel like one of those universal human desires. Even the concept of privacy as we know it, was foreign to the Middle Ages.