“I learned me 12 times table by the time I was 9. It didn’t do me no harm!”

If you overlook the tick in his right cheek and the rictus grin, the certainty of the apocryphal London cabbie is reassuring. I bet it was he who told Michael Gove how maths should be taught.

People of my generation learned our times tables by rote when we were in junior school. I think I was well taught and I don’t know why the rote learning of times tables apparently disappeared from schools. It worked for me.

That is the point, though. It worked for me - but it didn’t work for everyone. Since my 1960s childhood, we have become more subtle and flexible in our approach. Teaching methods, ways of tackling tasks, the building blocks of fundamental learning: they work differently for different children.

Government pressure over the past two decades has forced teachers to teach specified schemes of work, in specified ways, so children reach specified levels at specified ages. We all know the result of using prescription to “drive up standards”: one searing proof lies in the fact that too many pupils get to secondary school with unsatisfactory levels of literacy or numeracy.

Constantly under the cosh from ministerial interference and hostile inspection, schools and teachers are invariably characterised as lowering standards. In truth, the lowering is more frequently caused by banal government prescription, benchmarks and floor targets. Teachers, like schools, come in all shapes and sizes, and some are better than others. But a teacher who really cannot be bothered to help children grow and make something of their potential is a rare beast indeed.

Nonetheless, yet another secretary of state is micromanaging. He is telling schools what to teach, when and how. How hollow those early promises of freedom and choice for schools now ring.

There was dissent within Gove’s national curriculum review panel. Andrew Pollard, its leading academic, described the proposed changes to the curriculum as “fatally flawed” and “overly prescriptive”. They are based on a misguided principle of linearity that insists children learn “first this, then that”. It is misguided because they don’t. Pupils learn at different speeds and in all kinds of different ways. Gifted teachers have always seen that and differentiated accordingly.

In 22 years of headship, I have lost count of the “new strategies” based on simplistic ministerial assumptions about how children learn. Gove’s proposed national curriculum goes one better, cherry-picking elements from all the highest performing systems in the world. Great idea; hopeless in practice. Smart schools have always nicked ideas from others: the posh term for it is “sharing good practice”. But you have to assimilate those ideas into what works for your school, with your children. A small group of advisers and a politician can’t do that for a whole nation.

There is nothing wrong with getting children to learn poems by heart. Nor to chant tables, as in the “old days”. But why must Gove insist that every child at a particular age has to do it? In a politician’s hands, the joy of poetry and the excitement of maths alike will rapidly become the drudgery of tedium. And narrow prescription will, as always, force teachers to teach uniformly, to the middle, so the brightest and the struggling alike get a raw deal. Again.

Here is a funny thing about the proposed curriculum. The government’s flagship schools - the academies - don’t have to follow it because they are (allegedly) independent. This suggests the great new plan is directed specifically at schools that have not converted. Are they the bad boys and girls, the slow learners in school terms? I think we should be told.

Will any politician ever find the courage to trust schools? To set the broad direction and then trust the profession to be creative, demanding, challenging and inspiring? I fear not.

From the quarter-century history of the national curriculum, teachers have learned the lessons of over-prescription and curricular overload. They have learned the hard way, by having to deal with the fallout. I have always believed people should learn from history. I hope my pupils do. But I fear politicians never will. They are always so sure they know better.

Dr Bernard Trafford is head of Newcastle upon Tyne’s Royal Grammar School. The views expressed here are personal.