“It’s just bant-ah!” said Tawny, a spiky work-dodger in Mr Bispham’s class in recent television edu-epic Educating the East End. “But it’s time for work-ah!” he sallied, and 30 pairs of eyes rolled so aggressively they nearly detached from their retinal tethers.

There has recently been an extraordinary rehabilitation of something that previously enjoyed a protected existence predicated on harmlessness: banter. A case in point is the teacher who agreed by “mutual consent” not to return to his job after his vocal and public renunciation of banter in the classroom when it was used to alienate or marginalise other students.

But what role does - or should - banter have in the classroom?

I remember one big-boned pupil who took every opportunity to loudly regale everyone with his often edgy opinions on race, gender and class. There wasn’t a thought too ephemeral that he wouldn’t instantly download it into his mouth and launch it into the crisp silence of a busy, focused class.

In one instance, he told anyone in range that he had been baptised at the weekend. “Was it at SeaWorld?” replied a contemporary.

The class detonated; the boy fell silent for perhaps the first time in his life as the monkey troops whooped and shrieked with pleasure at the wound. Ah, the banter.

The thing is, despite a small part of me giving, inside my mind, a polite golf clap at the swift wit of the return, it needed to be caught and pilloried as much as any other behaviour. Banter is rarely without victim, and at its heart lies the motive of cruelty.

I grew up in a social circle where not a moment passed without some harrowing of character between me and my peers. We baited and slashed each other as a lingua franca. The difference was that my friends and I did so from a background of profound trust and camaraderie. Were any hit to draw blood, we would have been the first to apply triage.

That telepathy of motive doesn’t exist outside the terrarium of close friendship groups. In fact, different groups frequently display a variety of norms and boundaries to one another.

Take the n-word. This word is a shibboleth for a group of boys I teach. It’s the n-bomb. If a boy outside that group were to drop the word carelessly, it would turn into a real bomb. One man’s banter is fuel for another’s fire.

So do we ban banter, as the aforementioned teacher suggested? Impossible. You might as well try to ban cruelty. You can contain it, reduce it, react to it, train against its deployment. But until we solve all the greater universal maladies, banter will remain.

What good teachers already do is refuse to allow cruelty to disguise itself as muscular, burly banter. By all means ban banter as an excuse, because it’s simply one reason among many to hurt other people for the entertainment of the crowds.