“I was talking to this chap in the pub, and he said ... ”.

I don’t know how my governors would react if I started basing my vision for the school on the basis of the odd conversation en passant, but I suspect they’d be unimpressed. They might hope I listen to parents but would be dubious if I based a massive policy shift on the comments of one vociferous dad who bent my ear in the interval of the school play.

Yet I fear that changes to national policy seem to be dictated by a minister’s gut feelings or by those of someone with “access”.

The trouble with education, of course, is that everyone is an expert. We all went to school and, whether the experience was good, bad or indifferent, we have a view.

This form of vox pop politics is a relatively recent phenomenon. One can barely imagine old-fashioned high Tories venturing into the street, let alone meeting people. John Major’s soapbox was an embarrassingly futile gesture. Tony Blair indulged a little, but it was David Cameron, during the last election campaign, who insisted on telling the country what the ordinary chap in Bristol thought about the health service.

I’m all for politicians being in touch with what people think - it would be a novelty. It’s the selective nature of their opinion harvesting that is dangerous. Even when ministers find a guru on a particular topic, they tend to seize on that view and only heed the bit they want to hear.

Take Sir Michael Wilshaw, celebrated Clint Eastwood fan and tough guy head of Mossbourne Academy. Politicians of all complexions are in awe of his uncompromising line on discipline, attendance and uniform, and praise to the skies his pupils’ achievements. So they should.

But when he observed that Michael Gove’s planned new EBac curriculum would be unsuitable for as many as half the children in his or any other comprehensive, it seems ministers became selectively deaf.

In recent months, we independent school heads have heard the education secretary urging us to share our DNA and Lord Adonis complaining that we never did when he asked. But neither of them has ever analysed that DNA. They think our success is all about smart uniforms, house and prefect systems and competitive sport. But these are merely symptoms of a deeper contract between pupil, home and school to co-operate obsessively in the quest for success. Moreover, parents are making a financial commitment to their child’s education.

Meanwhile, Michael Gove is unnervingly certain about what history should consist of. And the schools minister is convinced the only way to teach reading is through synthetic phonics. End of discussion.

All this sits uncomfortably with the Coalition’s stated aims. After 13 years of Labour rule, schools were drowning under the remorseless tide of paperwork, targets, strategies and micromanagement more often connected to social issues than to education. “Initiativitis” paralysed the education system.

The new Government promised to end all that. Mr Gove castigated the 500-page national curriculum (it felt like more), promising a slimmed-down core. He said he would set schools free, give them autonomy and real power to make choices, manipulate budgets and devise curricula that suited them and their pupils. All this was vital, and long overdue.

I’m grateful to see a government with the courage to do what is needed. Its opponents characterise the public spending cuts as demonstrating Tory hatred of public services. That’s unworthy. The country had long been living beyond its means. The notion of spending our way out of recession is foolhardy. More than a decade ago, I had to cope with falling rolls in a school: we had to cut back and make redundancies. It was a truly awful time, but we did what was necessary and we emerged from it strong and ready to move forward.

So tough is good, but then I despair when ministers lose the courage to trust schools and start micromanaging again. Politicians, lacking a sense of irony, seldom see how close they are to repeating their predecessors’ mistakes, and not just education ministers. When Nick Clegg, a highly educated man, lambasts the country’s top universities for being “elitist”, we should be very afraid. If it weren’t so dangerous to higher education’s future, it would be laughable.

The profession must keep telling politicians what they need to hear, not what they want to hear. And let’s put an end to vox- pop policy making. I had that Ken Baker in the back of my cab once ...

Dr Bernard Trafford is head of the Royal Grammar School, Newcastle upon Tyne. His paper for the National Education Trust, Desperately Seeking our DNA: what independent schools bring to the free schools debate, is at http:bit.lyh8euFy.