The first glyph of every line – a hint at a cipher?

[JoJo_Jost]

When I first saw the page initial and subsequently the paragraph initial strong leanings toward ‘normal’ words being prefixed by a gallows, I imagined it was a means to flag to the reader which cipher table to begin with for that page/paragraph. A “Pch” meant use table P’s ch row to start.

Could line initial prefixes then indicate using starting that line with the ‘y’ or ‘d’ etc… row in the same encryption table?

I’ve also wondered if a space was only changing rows in a table such that each ch of consecutive chol chor or each d of daiin dain were different plaintext letters or syllables.

As for labelese, I always wondered if the ‘o’ table consisted of letters that also act as numerals.

Your hypothesis about multiple cipher tables is interesting, as it might align with my observations in the data. However, I am still looking for a simpler solution because, as you yourself say, this type of cipher is somewhat anachronistic, having only been (officially) described 30 to 60 years later. Perhaps, however, it was already known in 1430, or the VMS is an early precursor, or the vellum lay in a cellar for so long until someone misused it for testing purposes, which would explain the different developments of the cipher – who knows .

But I can mention a few figures that I did not include in the main post, as they are preliminary but could be relevant to your idea.

Bigram differences between the various markers

Idea: If the seven initial markers were indeed different cipher tables (or different rows within a table, or something similar), then one indication might be that the internal bigram statistics differ between the seven groups.
And that is why I have carried out a comparison

   

Some bigrams appear to be highly group-specific (op, yp, ed); there are clear differences here. Others seem to be distributed more uniformly, such as (yk).

This is likely what would result if p- and o-rows were created from partially overlapping but partially distinct sets of glyphs – in other words, precisely the pattern that such a table/row-switching model would produce when generating an otherwise very homogeneous cipher (so that one cannot simply recognise that they are different tables or the like).

[I would like to emphasise that this investigation is still preliminary.]

Regarding your observation concerning the start of a paragraph
Your suggestion that ‘Pch’ means ‘Table P, row ch used at the start’ aligns
with what can be structurally interpreted there.

On the idea of the o-table as digits

This is an interesting hypothesis given the distribution I see for "o" in my data: just under 36% of all lines beginning with "o" are found in the Astro section, the section with the most label-like short tokens. If "o" were to be a subsystem used for digits and labels, this concentration would not be a coincidence.

The "o" lines in the Astro section should exhibit different distributions of token lengths (shorter, more repetitive) than “o” lines in Herbal or Pharma. That would then to be checked.

On the idea of the space as a switch. I’m also struggling with the spaces. At the moment, I believe they do not form word boundaries – but I cannot prove it.

But if one imagines that the word boundary itself signals a change to a different row within a table, this could explain the unusually high repetition of the same surface forms. Or am I mistaken there?

Then e.g. chol chor chol sequences an other would not be repetitions, but simply successive plaintext values that happen to share a cipher surface. 

However, I haven’t yet found a way to test this. One would have to consider what "signature" such a type of structure would leave behind. I’m thinking about it; however, as I said, I’m looking for a simpler logic...