I can't remember it all that well, but skimming it I remember that what I found most interesting about it was the stuff about impersonality, which chimed with remarks made or written by Flaubert and Joyce about the artist disappearing into the creation
"What happens is a continual surrender of himself as he is at the moment to something which is more valuable. The progress of an artist is a continual self-sacrifice, a continual extinction of personality."
I had a (very) vague idea for a PhD about literature and impersonality, linking it perhaps to the transcendence of self offered (allegedly) by meditation and psychedelics, and I would have certainly cited Eliot on this stuff...
My scant experience of drawing/painting and music production makes me think that the artist in the process of creation, while drawing on their personality and having some sort of creative parameters defined by it, doesn't necessarily consciously express it and IS caught up in and constrained by a medium that is outside of them, bigger than them, and that this is a good thing
Yeats another figure I remember talking about this: "Even when the poet seems most himself . . . he is never the bundle of accident and incoherence that sits down to breakfast; he has been reborn as an idea, something intended, complete."