There is some great info and suggestions in this thread, thanks to all! I'm going to have to read it a few more times.
Totally agree about "YouTube learning". The tendency is often to gloss over the basics. Or to crawl through just enough of the basics to get somebody started... at a snails pace... but, still never fully explain basic theory.
Having never learned any of this in school (other than a semester of music in 7th or 8th grade as one of those "rotating elective" kind of things), it's been a slow process. People start talking about the circle of fifths as if it's the end-all of things... but, for me, I just looked at it and said, "Why?" I can't just accept that it IS, I wanted to know the why, and that info is harder to find in a digestible form.
But, I'm getting there.
I'm a driving instructor by day, so I can relate that to what I'm up against here. Learning to drive involves a lot of different processes. Learning the rules of the road, practicing physical car control skills, and learning to deal with traffic in the real world just to gloss over a few. As an instructor, I try to start from the basics and work up. You can't learn to deal with traffic until you've got car control and know the rules! (but, an awful lot of parents try to teach their kids that way, anyway)
Same with learning music. You can't expect to be a good musician if you don't "learn the rules" and "practice the physical skills". The rules take constant reinforcement. The skills take constant and ever-expanding practice.
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