Cipher or unknown language - historical perspective

[oshfdk]

And there is literally nowhere the definite evidence that all or most letters needed 2 strokes.
In that example picture, there are many characters shown where no second "landing" after an offset is visible.

I'm not sure if you need other people's opinions or not, but in case you do, here's mine: the shapes of most Voynichese letters could be produced with one stroke using some special techniques and writing implements. But the strokes would have looked quite differently if this was the case. To me it's absolutely certain that almost all glyphs in the manuscript were actually written using more than one stroke, with the exception of e and i.