Starkey's insult to Connor was a step to far, but in the classroom, should teachers be able to talk back to students?

Yes, like Starkey says, they've had too much of the milk of human kindness,students need tough love.

No, students need encouragement, not insults! They learn from praise, insulting them will just lead to worse behaviour.

Maybe, it depends on the kind of response, there's a big difference between scolding a student and just insulting them.