How fast could a scribe write a Voynich like text?

[oshfdk]

While I agree that it can't be used as a definitive way to exclude a purpose - indeed, it might even be purposeless, people are weird and you are right that some people spend months and years on a hobby (including some of the posters here on the topic of the manuscript!) - the assessment of motive does have impact on how likely a hypothesis should be judged to be. For instance, a hoax made for monetary gain you can knock out in a month needs to be far less lucrative in the mind of the forger than one that takes you years.

But this also depends on the circumstances of the hoaxer. If it was person who had plenty of time but no extra money (which would explain the poor quality materials), then it's still quite possible that a lot of time was spent on an object or relatively low value. Also, if the idea was to forge a specific book of roughly known size, then the forger had to produce 240+ pages one way or the other (again, explaining the desire to save on materials). I'm not sure we can assess the likelihood of different plausible scenarios, there are just too many unknowns. It may be possible to separate implausible from plausible, but I think that's about it without some additional data.