I get in a certain amount of trouble for pointing out that sometimes players who don't practice turn out to be more insightful about music than people who think they know what they are doing because they can play all the right notes.
This morning was another instance of how this works: A young man who loves the "Moonlight" Sonata, as do I, played through the first 2/3 of the first movement. Was there any passage that particularly bothered him, or stood out as different from all the rest? He noted the passage where the piece happens to modulate to the key of F# minor--I say "happens to" because I don't believe in the concept as taught in theory class.
Making the music coherent to him required that I attend to its inner workings, something I had never had to do because I have "no trouble" playing the notes. But sometimes "no trouble" is trouble in disguise, or at least non-comprehension. Just because I can get away without noticing what holds it together doesn't mean I "get" it.
I am struck by how often it is the students who lead me to real learning.