The prisoner scenario: a though experiment

[oshfdk]

You can be a prisoner and not "behind bars". You could just be in someone's castle and not permitted to leave for whatever reason, a debt of some sort, your existence is problematic politically.. so on

The main conditions for the prisoner scenario are you'll be punished if you write manuscripts and you are being constantly monitored. If yes to both, this can explain the ink density variation, occasional jitter, small format, mistakes in images and alignment - basically the author was covertly doing something for which she or he could be severely punished, which could explain a lot of inconsistencies, including possible use of poor quality quills and inks, strange writing system, strong cipher, etc.

If either or both of these conditions are not true, all these features require a separate explanation and then the prisoner scenario doesn't have much to offer by itself. Maybe it can still explain why the manuscript is this long, just because prisoners have plenty of time and little to entertain themselves.