On reflection, I’m glad that driving examiners know how to drive. I think it’s a helpful skill on those occasions when they have to wrest the steering wheel out of the hands of an incompetent driver.

I’m similarly pleased that the examiners who approve trainee dentists know how to fix people’s teeth themselves. It means that our dentists have to meet professional standards, rather than merely showing enthusiasm and a childhood talent for mending things.

Then there’s Ofsted inspectors. We are one of those schools that recently got a letter telling us that - unless we screw something up - we shan’t be inspected for a year or more. Of course, some zealot could always vent bile on the website Ofsted calls Parent View. But failing that, we have earned a year-long breathing space to work out what the inspectors will be looking for the next time they call.

The new schedule, we gather, is all about the classroom, which on the surface will strike lots of people as a “very good thing”. After all, under the old Ofsted regime, you sometimes got the feeling that inspectors could have stayed at home and phoned in their reports based on what their desktop computer told them. It was essentially an evaluation of your spreadsheets. With the old Ofsted approach, there were some schools where local inside knowledge warned in hushed whispers not to send your own children there, despite their stratospheric results. There was a locally accepted rhetoric and reality: Ofsted versus the people.

So the proposal of the chief inspector of schools, Sir Michael Wilshaw, that inspection should be all about the actual teaching seems superficially sensible, doesn’t it? Well yes, superficially - if superficial is what we’re after. Because we’re told inspectors’ judgements are now all about pupil progress. As I’ve written previously, this concept of demonstrating progress in a 20-minute slice of a lesson can only lead to superficial teaching. An inspector walks in and I’ll play the game, pointing knowingly at the learning objective and asking pupils dutifully to quack their progress.

But who is it that’s making a judgement about the quality of my teaching? What’s their credibility? Just as I want those who examine pilots to know how to fly a plane, I’d like the reassurance that inspectors know how to teach. If they tell me that I’m not differentiating for the full range of abilities, not setting challenging targets, not paying sufficient attention to whole-school literacy or spiritual, moral, social and cultural concerns, I think I’m entitled to say: “Really? Could you show me how it’s done then, please?”

This matters because - clinging to a very, very old-fashioned notion - I believe that part of Ofsted’s purpose should be to help us improve our schools. So I don’t want to be judged on my teaching by people who fled the classroom before the latest whims and fads solidified into orthodoxy. In education, credibility matters. We have a chief inspector who was a successful headteacher, so why not inspectors with some kind of MOT certificate to reassure us that - when backs are to the whiteboard - they themselves can teach?

Geoff Barton’s Counterblasts: Shouldn’t Ofsted be helping us to improve our schools? is published by the National Education Trust.