Kenneth Clarke is a misunderstood political figure. "Good old Ken ... he's not very hot on the policy detail" seems to be the general view. And, of course, there is plenty of evidence to suggest that Mr Clarke enters a broadcasting studio without checking on the latest facts and figures or indeed his party's own policies. He enjoys the art of political interviews and is one of the better artists; the idea of preparing for such events is anathema to him.
In extemporising during an interview on Sunday, he described the Conservatives' plans to scrap inheritance tax as an aspiration rather than a commitment. He did not seem to realise that he was indicating quite a shift. Aspirations are rarely implemented. Instead, the "get-out clauses" are nearly always deployed.
Not so long ago, Gordon Brown "aspired" to match the spending levels per pupil of private schools, but he will not have the resources to implement his aspiration. In contrast, David Cameron and George Osborne remain committed to scrapping inheritance tax, although I note they wisely make no pledge to implement the policy early in a Parliament. In my view, they would be wiser to scrap it altogether. Mr Clarke evidently agrees.
Ironically, this is why his image of casual indiscipline is misleading. In being undisciplined, he demonstrates a form of disciplined rectitude which he has applied consistently to economic policy. In the 2005 Tory leadership election contest, he bravely warned activists in some detail that cutting taxes was not an easy option – not that such modernising candour got him very far as a leadership candidate.
Mr Clarke is rigorous on "tax and spend". He remains a passionate supporter of Geoffrey Howe's 1981 Budget, which put up some taxes and cut public spending in the height of a recession. The 1981 Budget has been something of a model for the current leadership's response to this latest recession, with its unique opposition to any fiscal stimulus and advocacy of cuts in some proposed spending.
The current recession is very different from the inflationary crises that arose in the late 1970s and early 1980s, but that is another story. Mr Clarke has always been one for keeping an alert eye on public spending (and sometimes when he was Chancellor an over-alert eye). But at least he was consistent and viewed "tax and spend" with a forensic seriousness. In his final Budget before the 1997 election, Tony Blair and Gordon Brown were both convinced that Mr Clarke would offer a big pre-election cut in income tax. They were ready with their response, which would have been to support any reduction, however big. Some cabinet ministers and Tory MPs in marginal seats were also eagerly looking forward to a pre-election bribe.
Mr Clarke did not deliver. Instead, he announced some relatively small tax cuts along with a spending round he described as "eye-wateringly tight". Mr Clarke likes a good laugh but he stuck to his principles and played Mr Scrooge at the Treasury. As a result, his presence on the front bench gives the Conservatives credibility, but only if the policies that accompany his presence are credible.
As I wrote on Friday, Mr Cameron has achieved a tonal consistency with his claim that "Labour's debt crisis" is so bad that a Tory government would have to take some tough decisions. Today, he will make another speech on regulation arguing that an apparent crisis of capitalism does not represent a fundamental ideological challenge to his party. As the Tories have always highlighted their support for law and order, Mr Cameron will propose more effective regulation and punishment for those that break the rules. However, he is deliberately light on the detail.
The Conservatives hope that tonal precision will get them through an election campaign. It will not do so, and Mr Clarke's intervention at the weekend highlights one of the dangers of a policy vacuum. Before long, the vacuum is filled with unwelcome policy declarations.
In opting for a policy-light approach, the Tory leadership has left behind the New Labour manual for winning elections. I have long thought it would be wise for them to discard this particular recipe for election victories, partly because we are no longer in the mid-1990s when it was first applied. Yet one area of New Labour preparation is worthy of emulation. It entered the 1997 election with detailed policies. A lot of these policies were tiny and incremental, but they had been worked through.
Mr Blair inherited a mountain of policies when he became leader. I recall him telling me that he spent one recess going through every single policy in painstaking detail, analysing which needed more work, which could cause difficulty in an election campaign and which should be dropped. It was out of that exercise, for example, that he proposed controversially a referendum on a Scottish Parliament. He did not think he could get through an election campaign without making such a pledge.
But where Mr Blair and Mr Brown avoided making detailed policy decisions in advance, they ended up in deep trouble when in government. Tonally, Mr Blair indicated at times that he was pro-European; that was not enough. In government, he never had the ammunition to be more pro-European. Similarly, he wanted to "modernise" welfare but avoided policy detail and never succeeded in implementing radical reforms. Policy detail is necessary to get party leaders through the scrutiny of election campaigns and in order to be effective in government.
Policy making is the most difficult job in politics, not least when party activists yearn for policies that would not be credible in the current economic climate. Making speeches about tone are important, and I can see why Mr Cameron seeks to clear the ground in his speeches over these few weeks. But he will need to cover the ground with some detail after that, or else the confusion over the past 48 hours will arise again – and there is a limit to how many confused messages voters will tolerate when it comes to tax and spend.