I take your point about knowing the rules before breaking them but in my case it turned out that I knew a lot of them before consciously studying 'music theory'.

I'm self taught and have played professionally and semi professionally for decades. I never earned enough to have serious tax problems and just when I was getting too old to enjoy performing I stumbled into teaching. I could bluff my way with theory, I'd taught myself enough to be able to read guitar and vocal scores, but I had to buckle down and learn ABRSM theory when I was asked to teach it. I was surprised to discover that, other than the vocabulary, there was nothing in grades 1 to 5 that I hadn't already encountered.

There must be a lot of musicians out there who will already know 'the rules' without knowing that they know them. (Scary shades of Rundsfelt!)

I sometimes wonder if we do students that much of a favour when we force teach them stuff which, if they just played and played and played for a couple of decades, would become obvious. Certainly music students have a different perception of the subject than I have. I suspect I've had a less painful experience.