Hi a quick FYI.
I used the iPad Pro Pencil yesterday to make annotations in PDFs prior to & during rehearsal yesterday and yes the pencil works nicely!
It has much finer point than a finger (no kidding) or stylus, and being pencil-like I find it easier to make legible notes (even though I do have the penmanship skills of a 6 year old)
The pencil is fairly long so you will need to find a place to store it without it rolling away, behind the ear won't really work

Digging Bandhelper...