Choice of glyphs

[-JKP-]

Here's a Latin excerpt that shows the frequency of the Latin y abbreviation at the beginnings and ends of words (most scribes used it a little more often at the ends than at the beginnings). I have marked them in red:

   

I also marked two occurrences of the b9 abbreviation (-bus) and of the -tis abbreviation (which is similar to -ris m and -cis g). There are also numerous tail-macrons and bar macrons that cross through ascenders (as in "v[e]l").

This is very much the same pattern we see in the VMS and because of its position at the ends of numerous tokens, I am suspicious that VMS dy is intended to look like (or perhaps function like) Latin by.