Quote:This is clever, although without thinking about it too much it's not clear that it would be fully invertible once you split the consonants and vowels into separate rows, since you would then have more numbers than letters within each row.
No, each row is numbered separately:
B,C,D,F... -> 1,2,3,4... -> ciphertext consonants
A,E,I,O... -> 1,2,3,4... -> ciphertext vowels
Since the decrypter knows that consonants are encoded with consonants only, and vowels - with vowels only, he uses the consonant row whenever he encounters a consonant in the ciphertext, and the vowel row whenever he encounters the vowel. This way the cipher is unambigously reversible.
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Of course the examples that I provided are not meant to be claimed close to Voynichese, they are just two worked out offhand as suitable examples for a "pronounceable ciphertext".
Personally I expect that the most productive approach to decrypting Voynich is the theory-independent one - since it elegantly circumvents the possible pitfalls of "cipher" and "language" theories by just postponing their application until some semantic relations are established or at least guessed between some Voynichese vords and certain objects or notions. Contextual analysis may help to trace those relations.