Personally, I prefer calling it "Juggling", but whatever turns your crank. :)

I do not know for certain, but based on my own experience and the experience of
another high level bard friend of mine, it is dexterity, not charisma that
affects your missed notes.

My friend was a level 30 bard (before he retired recently), and he was so
convinced as to the importance of dex that he wore items to boost his dexterity
over 120. One of these items was the Grotesque Mask, which actually lowers your
charisma, giving you an indication as to how important he felt Dexterity was.

Also, the level of the song relative to your own level is very important in
determining how often you miss notes, as well as your skill with the
instrument. The first time I tried to play Denon's Disruptive Discord with my
horn, I missed about 20 notes in a row before I finally got the song going. Now
that I am better in Brass and higher in level, I miss much less frequently.
Also, I missed much less often when I sang instead of using the horn.

Is this answer definative? No. But I would be very very surprised if Charisma
was the determining factor rather than Dexterity.

Strength is still THE most important bard stat though, in my opinion.

Jyzan