Severus raises a disapproving eyebrow, but lets him finish. Then he spells the cabbage into the two grids again, one after the other. "As you've expressed a disinclination to return to teaching, I won't immediately subject you to the cacophony charm to underline the point, but it's generally a mistake to introduce music to one's brewing until the bones of one's hand have learned the essential rhythm. Do you see how the width of your strokes was informed by the altering tempo?"