Teaching should definitely not be done by the "most capable on the subject", it should be done by those who are the best educators (with "best" being based on s

Teaching should definitely not be done by the "most capable on the subject", it should be done by those who are the best educators (with "best" being based on some metrics relating to student outcomes). Both roles are not the same. Just because someone is knowledgable about a subject doesn't mean they know how to convey that subject for consumption. Conversely I think that those who don't know as much about an entire subject but understand the material of a particular course very well could be better suited for the task of teaching than the "most capable".