Groove as a pattern of integrated clues

The concept of a musical "groove" alone should have tipped me off about what knowing is about. It's impossible to explain what a groove is, and impossible to pin down precisely what makes it up in any particular piece of music. Yet every good musician feels the groove, and can lay effortlessly into it with no more than a bar or two to inform him/her about the nature of it in a given piece. When one musician shifts the groove in the midst of a piece, the rest adapt almost instantly. I watch it happen every week, and sometimes get to participate in it. But it never ceases to amaze me. You could call it an oscillating bed of complex human interactions, in which every element is a feedback loop for every other. But that only makes it sound like everything it's not. "It's a feel thing," they say. Body clues. And it's the kind of thing that requires, for most people, an authoritative guide to learn.