Steve Troughton-Smith:

The new Apple Pencil gestures are pretty bad, accidentally invoked all the time; think I’m gonna disable it. Should have had a button.

I disabled mine. Turns out that I like to give my Pencil a single tap from time to time, which is more often registered as a double tap for some reason. Perhaps this happens when I move it around a little too vigorously, when preparing to use it, and the movement itself (with the shock of resting my palm on the iPad’s screen) registers as the first tap.