John Rentoul: Didn't do our prep, did we, Mr Cameron?

I won't labour the point, and I will one day entertain you with my long list of things that Tony Blair did wrong, I promise, but he was a successful prime minister who learned on the job. More than that, he wrote a lot of it down in a book so that others could spend less time on false starts than he did. Even more than that, David Cameron and many of his people have read the book, by the man they called, when they first arrived in Downing Street, "The Master".

In which case, a question must be asked. Did they take in a single word that Blair wrote? Cameron's failure to do the homework set for him by The Master was cruelly exposed by Evan Davis on the Today programme on Friday. It was as if the Prime Minister had mugged up on the wrong subject. He had read newspaper articles about New Labour's message discipline. So he knew that he had to have a "story". But he had not read the bit in A Journey about the interview Blair gave on his return from holiday in 2006, in which he brushed off a question about when he would stand down, thus triggering the Brownite coup. "One rule about giving interviews: never do it without knowing the answer to the obvious question. Sounds simple, but it's amazing how many times even the seasoned pro can walk in full of thoughts, full of great things to say, concentrating hard on what they want the story to be, without ever focusing on the answer to the one question they are bound to be asked."

So Cameron concentrated hard on what he wanted the story to be. It was quite an interesting story, namely that politicians have been too respectful of nursing as a profession to suggest that the people who practise it are anything but angels channelling Florence Nightingale through Nye Bevan. This is an important and well-timed observation, after a number of reports exposing failings in care, especially for the elderly. It is, on a superficial reading of the lessons of The Master, a "brave" position to take. Cameron might imagine that he was taking a risk with his rebranding of the Tories as the party of the NHS; that he was showing "leadership" at a time when public opinion might want to hear a hard truth about what Nigel Lawson called "the closest thing the English have to a religion".

The Prime Minister had even thought it through to the extent of backing up this interesting observation with a photo-opportunity with nurses at a Salford hospital. Oh, yes, and a policy. Some wonk in No 10 had worked out that the first question would be: "What are you going to do about it?" So Cameron imagined himself saying to Evan Davis that this was a very good question and he was glad he had been asked it. Because he had an answer, which was that he was going to tell nurses that they had to speak to patients once every hour. Guidelines on how to nurse, that was the policy.

It was at this point that the Prime Minister found himself staring at an exam question for which he had not prepared. Davis asked him why he promised to abolish Labour's top-down targets in the health service and was now imposing new top-down targets. Well, said Cameron, this isn't a target, this is "setting some standards at a national level". Surely, Davies persisted, it was not a matter for him to regulate the number of times nurses spoke to patients? Still answering a different question, about the importance of symbolism to a leader, he said that it was "the Prime Minister's job to speak up on issues that people care about".

It showed that he had failed to take Blair's lessons to heart. He might have read all that stuff about Blair and Brown endlessly working through their policy positions, and assumed that it was preening: that the real success of New Labour was a marketing exercise – in which case he has not understood it at all. He has no idea what the NHS should look like in 10 years' time, and by what mechanisms it would be achieved. Thus, he allowed Andrew Lansley to pursue two incompatible strategies at once: (a) tell NHS workers what they want to hear, and (b) plan the biggest structural reorganisation since 1948.

Now Lansley and Cameron are contradicting both strategies. That is not what triangulation was supposed to be about. Nurses do not want to hear politicians telling them how to do their job; nor were such diktats part of Lansley's half-baked plan to decentralise the health service. The plan to hand over NHS budgets to GPs looks like an attempt to follow the lessons of Labour's health reforms without understanding them at all. It is like a primary school pupil taking a sixth-former's economics essay and cutting it up and sticking it together to make a collage.

Blair understood – eventually – that self-sustaining reform of the NHS needs patients to have more power and to be able to choose between healthcare providers, but that national targets would be needed to enforce minimum standards for the foreseeable future.

There was a problem with that policy, which was how to overcome the conservative opposition of many people in the health service with a vested interest in keeping things as they are. Attitudes were changing, with research showing that competition saves lives – such as a London School of Economics study that showed hospitals facing local competition had better survival rates than those that did not.

Just as those reforms were reaching a critical mass, however, the Conservatives have messed them up, with the Liberal Democrats in the House of Lords now trying to remove the final traces of any threat to vested interests from the legislation.

Cameron has done his homework on schools – he was once the Tory education spokesman, after all – and in Michael Gove he has chosen someone who really has read and inwardly digested The Master's work. But on health he is trying to get by on last-minute cramming, and it shows.

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