Distinguishing Characters

[Mark Knowles]

And why would this phenomenon emerge only once with the Voynich and not independently in other instances?

The VM was done for fun, not necessity.

And why does the situation of "fun" occur only once in the case of the Voynich manuscript and in no other documents. Why weren't there other people developing complex ciphers for fun at that time? Again you still have this notion of Voynichese having no antecedence and having just emerged out of the blue.