It’s easy to describe small shifts in a movement as “subtle.” As in, a teeny little tilt of your pelvis this way or that.
But let’s remember: what’s the point of these shifts unless they’re producing a notable shift in something? That something may be a felt experience; it may be the student just needs to trust the teacher that the shift is the way to go.
Either way, the point isn’t subtlety; it’s the obvious.
Consider assessing if milk is still okay or if it’s spoiled. It may have shifted color, but just a little bit. If you’re only using your eyes, you’ll describe the shift from fresh to spoiled as subtle.
But if you’re using your nose, it’s obvious.
Here’s this same thought in a video if you’d prefer: https://instagram.com/p/BpATvgkBfPK/