How fast could a scribe write a Voynich like text?

[dexdex]

I definitely would consider the enciphered text less likely than gibberish if producing the enciphered text takes 50 times longer. And I would consider it even less likely if it takes a hundred times longer. Is it eliminating possibilities, no - but forming an opinion without a decipherment is worthwhile both from a personal (what I feel) and practical (What's worth considering first) point of view. This question has bearing on forming an opinion, because the times of production are obviously gonna differ - but I am unable to say exactly how much, so I am unable to update my balance of probabilities on the matter. Which is why I'm curious if someone more knowledgeable can pitch in.

What about the presence of artwork?  Does the manuscript having artwork make you think the text is more likely to be an encryption or more likely to be gibberish?  How does the Voynich Manuscript compare to other encrypted manuscripts with artwork?

I am entirely unsure about that. I don't think having artwork really hampers or helps any theory. The word wrapping around artworks suggests that the artwork and writing were applied at the same time. The Gaskell&Bowern experiment suggests the peculiar behaviour of word wrapping around images is something people writing gibberish do replicate, but there are ways around this for enciphered or meaningful text (nulls, spaces being nonessential etc); that has recently impacted my judgment but I wasn't convinced about it when I first read the study 6 months ago so I understand people can have differing opinions on if it matters.