The Cardan grille approach to the Voynich MS taken to the next level

[Davidsch]

Another option that is not discussed but can be a method that gives similar results as a Cardan Grille and that is using sequences that count up to a particular point, then mutate, and then fall back to a predefined position which is often the same or shows an altered primary position (the latter case can be perhaps seen in the Rohonc, but that's another unfinished story).
Anyhow, the final result will resemble a grille with nullified text, but it isn't.