The same is true of the working families tax credit, 18 months old now, and still, by the Government's own estimate, uncollected by 300,000 of the poorest citizens. As a spokeswoman at the Chartered Institute of Taxation notably remarked: "The trouble with tax credits is that people have to know about them."
What an opportunity the Chancellor has just lost to give people a bit of control of their lives. He could, for example, have abolished tax on savings and investments for basic-rate taxpayers: many of the old and poor never get round to reclaiming tax deducted at source. A pity, too, that he didn't grasp the nettle of making child care tax deductible - he might have touched the voting intention of many working mums.
What then of the Government's attitude to marriage? New statistics tell us that the institution is on the wane. But in an era of planned obsolescence and disposable relationships it remains a tribute that this bedrock of family still attracts the quiet majority.
Government policy is divided and wandering. The Prime Minister caused dissension in the ranks when he pronounced in favour of marriage, describing it as "the foundation of a strong and stable society, and the best framework within which to raise children". Teachers in England are now required to extol the virtues of marriage, along with advice on parental responsibilities and the impact on families of separatio or divorce, as part of the first national framework for personal, social and health education.
Yet many Government spokespersons suggest that overt support for the institution of marriage stigmatises children growing up in other family arrangements or none - a genuflection to political expediency and shaming moral relativism.
The nanny state's latest attempt to address the soaring problem of teenage pregnancies sends out mixed messages too. The pilot scheme provides free full-time child care for the 15-year-old mum returning to study. If, however, the same girl waits until she is 17 and at college she must find her own. How much fairer to other poor families to empower schools financially to provide all-day cr ches on site and to charge only those able to pay.
Recent research of practical interest to teachers comes from a leading developmental psychologist at Lancaster University. Two conclusions emerge: first, that there are critical periods in a child's development when close parental involvement is the most important influence. The years from seven to 11 are just such a key stage. If you haven't made it with your child by 11, he suggests, you've lost your chance.
Second, that the quality of a relationship between father and child at 11 is a good predictor for the child's subsequent school results and general behaviour. Findings show that children who had little contact with their fathers on average were more likely to give trouble by age 16, and that the gap in qualifications between those with earlier good and poor father contact was around 20 per cent.
Veils and vicars notwithstanding, more marriage could just help stability in the hard-pressed classroom.