Celebrating its liberation from the trammels of coalition, the government is in a hurry. The hundred days syndrome is an understandable weakness of a new administration, especially one with an uncertain majority, but it is no excuse for a headlong rush into a major piece of constitutional reform. That is what Chris Grayling, the leader of the house, is attempting with his proposal to introduce English votes for English laws through the arcane and obscure mechanism of amending the standing orders by which parliament is run. Devolving powers to Scotland, Wales and Northern Ireland has raised some big questions about the role of Westminster that deserve the kind of careful consideration, consensus and workability best achieved through a constitutional convention. Instead, this government is trying to bounce parliament into a change of lasting and possibly unintended consequences.

Getting legislation through parliament is unavoidably complicated. But the principle is easy: one member one vote. Not under Mr Grayling’s plan. That privileges some MPs with a second vote. If the Speaker certifies that a bill or a clause is relevant only to England or England and Wales, then English or English and Welsh MPs get a veto. It is not only the SNP that thinks this idea stinks.

English votes for English laws, an answer to the conundrum formerly known as the West Lothian question, undoubtedly speaks to a genuine sense of grievance, although not one with much basis in fact. According to the Commons library, almost all the legislation since 2001 has been passed with the support of a majority of English MPs as well as a majority in the Commons as a whole. Researchers counted 3,800 divisions. Less than 1% would have had a different outcome without Scottish votes. In fact, the power of Scottish MPs in particular either to obstruct laws the English want, or to force through ones that they reject, is almost entirely theoretical.

It is beginning to seem questionable whether the Tories appreciate that Westminster is the beating heart of the union

Nor are there many examples of governments whose majority rests only on Scottish MPs. Within the union, England is overwhelmingly dominant. Since 1945, only three governments with an overall majority did not have a majority among English MPs as well. That is one reason why there has never been much support for an English parliament, although there is swelling enthusiasm for regional devolution.

Although it is not limited to Conservatives, the sense of injustice among English voters has been unscrupulously encouraged by the Tories as a way of expressing discontent with the whole process of devolution. Although it was first raised by William Hague after Scottish and Welsh devolution in 1998, it has never been more obvious than on the morning after last autumn’s Scottish referendum, when David Cameron responded to the result not by celebrating a newly endorsed union strengthened by the no vote, but by reinventing Scotland as a problem for the English. He could not have played more effectively into the SNP narrative of betrayal that was in full flood again in the Commons on Thursday.

The Grayling proposals are supposed to be the answer to this inflamed demand for a theoretical fairness. They are to be rushed into force as if to meet some kind of emergency. The leader of the house has asked the MPs’ backbench procedure committee – which has not yet even had its first meeting – to report on his proposals in time for a vote in less than a fortnight. Perhaps he hopes that the Conservative majority on the committee will provide him with a fig leaf, something behind which he can hide the way he has exposed his utter disregard for the significance of his role.

It is not just parliament that has been demeaned. It is beginning to seem questionable whether the Conservatives appreciate that Westminster is the beating heart of the union. Two years ago, a former top Commons official, Sir William McKay, was asked to find a way of reflecting English and Welsh opinion within the existing legislative process. The Grayling proposals are based on his. But the McKay report expressly ruled out doing exactly what Mr Grayling wants to do: creating two tiers of MPs dependent on geography, opening the way for a deadlock between England and the rest of the UK. This is yet another piece of constitutional tinkering that is probably unworkable and certainly a threat to the United Kingdom. All governments say that the mechanics of democracy are dull, like the innards of the family car. It won’t seem like that when the big end goes on the motorway.