Don’t you really wonder what he “sees” when he closes his eyes and lets his fingers move over the keys?
As a non-musician, I am simply awed by what you and he and all the others who can put finger to instrument and create music do. You are all my heroes.
Yes, I wonder what he “sees” - and I know I never will - but to be clear:
I am the opposite of him. He, I suspect, is what Myers-Briggs would class as an SP, probably ISFP (artist/composer; just a guess).
I am an INTJ (scientist/mastermind; no, not criminal). For me, music is a mathematical language. Although I can and do devise melodies and harmonies spontaneously (especially in my sleep, which makes waking up frustrating, because they fade before I can get them down), I usually work from a self-imposed and demarcated system, usually a variation of modes or multiples of modes.
In other words, he works without theory; I work by means of theory.
That does not mean that I only use what I was taught. I actually do all sorts of things that I was not taught, but I work from a theoretical basis.
As a poet, you probably are acquainted with the idea, a la C. S. Lewis, that the great poets can break the rules because they know the rules by heart. It is like that: I did well with theory, so I know more or less what I am doing, even when I am doing it “wrong”.
Being that, I am a very poor instrumentalist, again unlike him. I plod along on the piano just to compose. The only instrument with which I am truly adept is voice, and being a very low bass, I can get into pretty much any ensemble I want without necessarily being the very best chorister - short of the small stand-alone elite groups. (True low basses are quite rare.)
SPs like him - assuming he is one - tend to live in the eternal moment, and make good performers. I am not a performer by temperament. I enjoy performing choral music as I am doing it because I love the music, not because I love performing live. (I had paralyzing stage fright for many months when I started this. Now I can go out in a packed arena, even without being fully prepared, and it’s just business as usual.)