Keith's vocalizing is more annoying than pleasant.
The true master of that is Tigran Hamassiyan. He took a lot from Keith's skill and other talented jazz musicians and created prog-jazz band. His skill is the next level from Keith by all means.
The Ventriloquism of Keith Jarrett
I've been a fan of his for eons and have many of his recordings. When I first heard him making his vocal noises during parts of his playing, I thought, 'WTF is that damn noise!?!" Hated it, but got used to it.
Just now, I thought I'd put on one of his live concerts via YouTube to listen to while working. On video, I hear his vocalization but don't really see his mouth moving at all.
It's like he's a ventriloquist or something.
Not important at all, but thought I'd share anyways.
Cheers, all.