You may perhaps have noted a contradiction in the last post about the relative slowness of the visual compared to the auditory response: For many players this is the rationale for playing from memory--remove the visual from the picture in order to free the ear.
That, however, is not the way it works for everyone.
I have had to learn to hear independent of the score. I have learned it mostly from listening to my students. When I hear as they hear I know I am really listening. I notice that when they know they are being heard with that precision they respond to sounds before they make them. I see them anticipate sounds; I note the subtle changes in touch that reflect their certainty that the piano keys do not produce uniform sounds.
Reading music is no longer a matter of discerning theoretical definitions and functions at work, but rather an invitation to engage my ear, one sound at a time, in propositions I cannot imagine, much less identify. This new reading is what enables me to revisit Schubert's F minor Impromptu, utterly transformed in the process.