It's not WHAT you learn but HOW.
"Mark", a 50s year old father, started learning from me this year, and so far has had a mere 4 lessons. Whilst he has played drums in bands, he has always wanted to learn piano. Naturally he has a great ear, but came to me as he wants to learn to read music.
During the last lesson, I asked Mark to play "Oh When The Saints Go Marching In", transposed into G major by ear with both hands. And it took a few goes but Mark was able to play it at the lesson.
It is a big ask to a beginner to play piano both hands, transpose music at sight, read and interpret music, play in time and use correct fingering all at the same time. But to me learning piano is not so much about the physical act of learning to play an instrument but about the willingness to learn something new, be willing to fail, keep trying and ultimately succeed.
Learning music to me is about wiring the brain to be able to play, sing, read, listen, and understand. It does not matter the content of the learning, but the act of engaging multiple parts of the brain simultaneously. As I said to Mark: "Many teachers would spend a term getting to where you are now. And you are beyond that in just 4 lessons."
(Also published on LinkedIn https://www.linkedin.com/pulse/its-what-you-learn-how-jonathan-harvey?trk=prof-post