There is a jumpy atmosphere in the Green Room. One more item, one more ad break, and then it is our turn. Three of us have been assembled for the skunk discussion. There is the anxious woman who went to prison for supplying heroin, who now tours schools telling children to say ‘no’ to everything, advocating zero tolerance. I sympathise with her anxiety and admire her endeavour, but statistically she is wasting her time. Neither education nor prohibition has ever been shown to reduce cannabis use. There is the smiley TV shrink, disgraced for allegedly attempting to pass off someone else’s work as his own, still clinging to his position as this programme’s tame psychiatrist, who has already informed me, giggling, that he means to be ‘controversial’. ‘The important thing,’ he says, ‘is that we mustn’t agree.’

And there is me, promoting a book about why so many of my generation smoked dope, hoping to make the case that honest, informed discussion is the best way to help young people negotiate the infamous ‘phase’.

I plead with the TV shrink as our slot approaches. ‘We need to help people distinguish between problematic and recreational drug use: we don’t want to panic them, or sound as though we don’t know what we’re talking about, do we?’

‘I think that’s too complicated,’ he says.