I too can relate well to that.

A couple of the guys I play with have views on this that I'll just state, because I still don't have the right recipe for me.

"The difference is that amateurs practice until they get it right, but professionals practice until they can't get it wrong". I think that's probably true, but I'm not sure it solves our problem.

In response to "how long did it take you to learn that [long and complex] song?", the reply was "I'd listened to it so many times and knew it so well that I only had to look at the music once and I could play it".

FWIW our jazz mentor is also keen that we "put away the music and just play", because reading the music, even a leadsheet, is a distraction.

I'm on a course at the moment that at present is focussing on the second above. "Don't yet touch your instrument; listen to as many versions of the song as you can find and maybe make a shortlist of favourite version, then actively listen to those; listen to the melody, to the drums, to the harmonies, to the rhythm. Then sing the song, even badly, partly just to prove to yourself that you know it. Only now pick up your instrument and start to play from what you can sing or along with your chosen version".

Now I've often wondered if I approach things from the "wrong end" and am starting to try this as an approach. I know not yet if it will work for me, but it makes sense. So often I hear something I like and I get the sheet music and try to learn it from that. But there are songs for which I've never seen the music and I can play them.

I'll be interested in how you or others find the course.

Jazz relative beginner, starting at a much older age than was helpful.
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