Yeah I've been doing dexterity excersises for a long time, I can play most of them fast, but that's because I know what I'm going to do ahead of time, with my pinky.
It's like my pinky and ring finger are best buds and don't go anywhere without each other. My pinky tends to hide right next to my ring when I'm not using it.
I've tried all kinds of dexterity exercises to help, yours is helping with the pinky being able to trill. It's not that it isn't accurate, it just tends to stay away from the fretboard.
By the way, how's the classical pieces coming along?
Sometimes I hit notes only dogs can hear.