Textual Complexity vs. Visual Simplicity

[Jorge_Stolfi]

So why is it so upside down in the Voynich?

Things are different today, and fast changing, in terms of school curricula and opportunities at home.  But in the time period in question, I would guess that most kids would get access to pen, ink, and paper only in school, and not even in the earliest graders. 

For most people, their experience with those instruments must have been limited to writing.  I guess that very few people, even among "scribal" professions (including secretaries, notaries, accountants, chroniclers, etc.) would ever try their hand at drawing.

So I think it is quite plausible that the VMS Scribe was well used to writing with quill on parchment, and had developed fair handwriting in Latin or whatever language he used, but had relatively little experience as illustrator.

All the best, --jorge