Analysing expressiveness in music (and painting?)

I accompanied my youngest to a piano masterclass in Trinity Conservatoire, London. The pianist Nigel Clayton expertly deconstructed performances of students; drilling down to the minutiae of playing: the weight of the fingers, the roll of the hand, the touch, pulling at the keys “claw-like” to invoke a nuanced difference in a dynamic to a subsequent -identical three note- motif. It was mesmerising and I hung on his every word. The analogies came thick and fast  - always illuminating the effect desired - the movement of Federer whilst waiting for a serve, for example. All the way through the sessions (each lasting ½ hour with a talented student), I kept wondering how this has any comparison with painting. The attention to such a high level of mechanical, emotional and, yes, technical detail that made me think. I believe there is such an accord and painting can only learn from it.  There can be so much more available to the expressive reach of the painter.