Hard to tell who are the Scribes and Pharisees these days. Used to be easy to label any religious zealot, call them a fanatic, and ignore their judgments.
That's what Jesus did, right? He lambasted those who looked for the worst in people, while ignoring their own, obvious faults.
Not much smarter than the dumbest students they will teach, it seems. But the answer really depends on the "research" we read. If this National Center on Education and the Economy (NCEE) publication is to be accorded the status of research, we may accept one of its many internal (and misleading) conclusions: "… there is mixed evidence on the number or type of courses a teacher takes and his or her performance in the classroom" (page 75).
Its authors are suggesting that we really don't know if teaching ability depends on the kinds of courses and how many of them a teacher takes, so they have no clear advice to give us on whether we would have better elementary school teachers if they took academic coursework in the subjects they taught.