English is a craft, and like any craft — woodworking, ceramics, bookbinding — I teach it through steady attention, judgement, and corrected attempt. The student reads closely, writes often, and studies under a tutor whose craft is passed on page by page. A rubric can answer writing that already exists. It can't produce it. Excellence comes from the cycle of writing, reading and editing — not from smoothing over errors to satisfy a rubric, but from paying attention to what caused them and working on that directly.
Such is the work of a craft: slow to acquire, durable once acquired.