I’m intrigued by those signs on the backs of lorries that say WELL DRIVEN? and then give a telephone number. I bet they get some funny calls. And what about serious ones - people actually phoning to pay a compliment? I doubt it. After all, what are you supposed to do, exactly?

I was hammering down the motorway the other day, and there in the outside lane was a truckload of fridge-freezers overtaking a slow coach and blocking all progress. Suddenly, the driver dropped back and pulled over to let me through. Could it really be happening?

As I forged ahead, I caught sight of that WELL DRIVEN? sign, and reached for my mobile. It’s illegal to use it while driving, of course, but this driver deserved a pat on the back, and if I didn’t ring straight away I’d forget the phone number.

But wait. What would I say? “Hello. You don’t know me, but I’m phoning because one of your lorriesI what do you mean which one? No, I’m afraid I didn’t get the registrationI” Oh well. Some other time.

And then I remembered what a headteacher had said the previous week. “Nobody ever thanks you when you get it right. They just grumble when you get it wrong.” He was referring to his staff, who tend to take his stress-busting innovations for granted. But he was also irritated by parents who never mentioned excellent teaching but complained if the beefburgers weren’t up to scratch.

He’s right, of course. So what’s the answer? Might I suggest sending children home with stickers that read: WELL TAUGHT? or HOW’S MY GERMAN? There would have to be a phone number for the school office, of course - and it would have to be a free number, because someone paying a compliment, like smiling, should cost nothing.

Most important, the school secretary would need retraining. After all, “I’m sorry, but you must have dialled the wrong number” is not an appropriate response to “Hello, I’m Henry’s dad, and I just want to thank you for the excellent job you’re all doing”. It’s not going to be easy, this bold experiment. Apart from the practical considerations, we would be cutting across human nature. But maybe it’s worth a try. Just don’t phone me if it turns out badly.