Seems that many pianists have their mannerisms, in public too (think this one might be ~~something like his internal metronome?)
Now if he'd started humming, instead ... Boffo! because:
Isn't it about Time for a reincarnation of Glenn Gould to appear?/we Miss him so..
Nice dynamics, reliable tempo and the little grace-notes/appogiatura in the JS come off clean.
Lucky, lucky.