Politicians and policy-makers should know by now the dangers of committing anything to paper. As the Hutton Inquiry has shown, it can always be used in evidence against you.
The present government, so keen on publishing goals and targets, is particularly vulnerable. As the Labour conference approaches, and the glimmerings of the next election appear on the horizon, it seems Labour's past promises are beginning to catch up with it.
So step into your time machine and set the dial to December 1996, just five months before Tony Blair made his triumphant entry into Downing Street.
Peer through the mists of time and you can just make out a thin, bespectacled academic putting the finishing touches to a lecture. Look closer and you will see that this professor of education is the very man destined to become policy adviser to Labour's new education secretary, David Blunkett, and later to Tony Blair in Downing Street.
Yes, this is Michael Barber, and his lecture for the Institute of Education is called "How to do the impossible: a guide for politicians with a passion for education".
It was both a blueprint for a Labour government and, in effect, a job application form. It worked for him, but have Labour's plans for education proved impossible?
Mr Barber's key recommendation was this: "The Government should focus on three or four central priorities and stick to them for several years."
David Blunkett took this to heart. It was not just education, education, education, but primary, primary, primary.
After so many years in opposition, Labour hit the ground running. At 8pm on Saturday May 3, the bank holiday weekend immediately after polling day, I was standing (as television correspondents do) outside the Department for Education. Minutes later David Blunkett emerged, looking exhausted. Fewer than 48 hours had passed since the polls had closed.
He had been appointed to the Cabinet early on Friday, arrived in Sanctuary Buildings by lunchtime, and apart from a few hours' sleep that night had been there ever since, even summoning senior civil servants to work over the weekend. A member of his private office said the department did not know what had hit it.
Within 10 days, Blunkett set the first-ever targets for key stage 2 Sats: 80 per cent to achieve the expected levels in English, and 75 per cent in mathematics, by 2002.
The next day two education bills were announced: one to reduce infant class sizes to 30, the second a wider measure called the Schools Standards and Framework Bill. The theme of the latter was "pressure and support".
Nursery education would be expanded, baseline testing and numeracy and literacy hours introduced, and targets set for year-on-year improvements in results. As a carrot for inner-city school improvement there were to be education action zones; the stick was the threat of "fresh starts" for failing schools.
Labour's first-term report card is mixed. Infant class sizes were reduced, although no targets were set for the junior school years. The numeracy and literacy hours have become the orthodoxy, although some believe these twin Goliaths have squashed the rest of the curriculum.
Other promises have been kept: there is a General Teaching Council and a National Grid for Learning. Individual Learning Accounts were introduced but, after a fraud scandal, were rapidly abandoned. Stephen Byers, the then schools minister, did "name and shame" 20 failing schools, but fresh starts did not always look so fresh as their heads resigned and their failings persisted.
Mr Blunkett put his neck on the block over the targets for 11-year-olds.
Luckily for him, he had moved on by 2002 when, despite considerable progress, they were missed. Truancy and exclusions figures were supposed to be reduced by a third. But the former have refused to budge significantly and ministers eventually admitted targets for the latter were a bad idea after all.
However, the Government successfully avoided the pitfalls of previous Labour administrations: the emphasis on "standards not structures" meant the bitter debates over grammar schools were not inflamed. Only one parental ballot over selection has taken place.
Yet, even before the end of its first term, Labour was already thinking about changing structures, by overhauling the "bog-standard comprehensive".
So the 2001 manifesto promised "a step change" in secondary schools. Each was to have "a clear mission". "Third way" language was more explicit: private-sector providers would support the public sector, with a spirit of enterprise encouraged.
But although business sponsors have supported specialist schools and the new city academies, the grander ideas for private-sector management of schools and local education authorities have not taken off.
Labour also extended its second term focus to further education colleges and universities with the controversial target of getting 50 per cent of young people into higher education by 2010. They promised educational maintenance allowances for students in FE and, although they may now regret it, they swore not to introduce university top-up fees.
Perhaps because Labour had ignored Michael Barber's advice to focus on a few priorities, the second term soon proved more accident-prone than the first. In August 2002 it all started to go wrong. Problems with the Criminal Records Bureau, then A-levels and the Qualifications and Curriculum Authority, led to a sense of panic and crisis and the departure of the then education secretary Estelle Morris.
As he heads for the party conference, Education Secretary Charles Clarke knows he is at the difficult delivery stage. The big-picture planning is done, now results are required.
The clarity of the focus on primary has been replaced by fire-fighting across a broader front. The school budget problems were a public relations disaster and shook public confidence. Meanwhile, concerns grow over exam-overload and the squeezing of creativity from the timetable.
The complex problems of 14-19 education (where removing one building brick threatens the whole structure) have been kicked towards Mike Tomlinson's independent inquiry. As for university top-up fees, he can only hide behind the technicality that the manifesto promise survives if they are not actually introduced until after the election.
There are signs the public is losing confidence in the Government. Despite consistently topping the opinion polls since 2001, Labour's overall lead has narrowed, and even disappeared in one example, since June. The Brent by-election result was a further shock to Labour's worried backbenchers, already anxious at the prospect of selling tuition fees on the doorstep.
The Iraq war may have been the decisive factor, but a YouGov.com poll in June 2003 showed a slight majority now believed public services had deteriorated under Labour. A Mori poll in July found 44 per cent thought things had got worse for Britain since 1997. It also showed Labour's long-term lead on education had evaporated.
So this is a testing time for Labour. Some targets have been hit, others proved too ambitious, and some were simply inappropriate. Some big promises have been met - there are more than 10,000 extra teachers, although a higher proportion now come from abroad - but to voters this perhaps matters less than a more general sense of how schools are doing.
At the conference, and in Parliament, the focus will be on university fees.
But just as crucial may be whether the delivery of their school reforms can satisfy voters that the upheavals of the last few years have been worthwhile.
Tony Blair may stand inside the very impressive pound;31 million Bexley Business Academy and declare he has "seen the future of education". But it will take more than a few showpieces to achieve a more general sense of well-being in schools.
Mike Baker is BBC News education correspondent
LABOUR'S MANIFESTO PROMISES
* Nursery places for all four-year-olds
* Cut infant class sizes to maximum of 30
* Baseline testing
* Numeracy and literacy hours
* Year-on-year targets for improvement
* 'Fresh start' for failing schools
* Raise the % of national income spent on education 2001
* 1500 specialist schools by 2006
* City academies
* Foreign language opportunities for primary pupils
* Extra 10,000 teachers
* Education maintenance allowances
* 50% of young people entering higher education by 2010
* No 'top-up fees'