Expert opinions about the VMS

[Sam G]

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if he strongly believes that there is a cipher at work, this must be according to a wider definition of cipher.

Okay.  Well, on that subject then, what I question is whether there is really a valid concept in the "wider definition of cipher" that is not already included in some other category.  It seems to me that you have two basic options that are compatible with the properties of the VMS text:

1) Essentially unencrypted language of some kind, whether of the "code book"/artificial language variety, or the unknown natural language variety.

2) Extremely verbose cipher with some kind of scrambling/transposition applied, or complete gibberish with a message hidden using steganography.  In these two cases the plaintext would have to be much shorter than the VMS text, and the labels would have to be meaningless.

I don't think there's anything else that can be concretely described that can't be ruled out.

I don't know if the 'stroke encoding' method once proposed by Elmar Vogt would count as a cipher, for example.
If it were something like that, at the end people might even be arguing whether it was a cipher or not even when it is solved.

It has been a while since I looked at it, but as I recall it was simply a variant of the verbose cipher idea, where the verbose encodings are determined by the strokes used to compose the plaintext letters.  It has the same problems with the verbose cipher idea generally (short words, no repeated sequences, one-word labels).