Can scribal hands be correlated to imagery? Let's look at faces!

[Jorge_Stolfi]

The scanned images may give casual viewers a false sense of scale.  The height of each page is actually ~23.5 cm.  Thus the drawings are smaller than one may think, and the traces are quite thin -- 0.1 mm or so on the drawings, a bit more on the text.   The face of a typical nymph is only ~3mm wide and ~5 mm tall.  Could you draw consistent faces of that size?  With a quill pen, on a rough vellum?