Whenever any controversy arises over porn, I think of my teacher friend who took the female half of her secondary school class for a sex ed lesson while the boys’ was delivered by a male teacher.

As the girls’ questions about what I was nostalgically pleased to learn is still called ‘doing it’ went on, a light dawned. “You do realise,” my friend said hesitantly, “that you’re supposed to enjoy it?” A dozen suspicious and baffled faces stared back at her. This, it seemed, was new information to them all. She spent the next hour deconstructing various myths and painful practices they and their boyfriends had come to define, thanks to barely filtered access to all sorts of porn, as well within normal adolescent activity.

Lucy Mangan says we should all “think twice” before considering porn harmless