Hi All,
With the understanding that this is long before the age of
standardisation of anything, and one author's table of ornaments is not
necessarily what another composer would have, and performers would
naturally have taken great liberties with interpretation of signs. Not
until 19c did people become very rigid about ornaments and signs. I
write speaking as a harpsichord player myself.
As an aside, but related, to this day nobody really has any clear idea
what the single and double strokes on stems that are ornament signs in
English Virginal Music really mean. There are dozens of different opinions.
As for whether trills and shakes start on the principal note or not,
that is an Eternal Debate that will never be resolved.
Isn't there an article here about making new ornaments for noteheads,
for 18c French music in particular?
https://lilypondblog.org/2013/08/adding-ornamentations-to-note-heads-part-1/Andrew