IN a cabinet of clodhoppers he is a twinkletoes, a Fred Astaire among Fred Flintstones.

Step forward Vince Cable, Business Secretary in the Coalition Government, former Strictly Come Dancing contestant and pain in the Tory posterior.

His blue-rosetted partners in the Coalition Government would dearly love Mr Cable to foxtrot off into the wilderness. Nick Clegg, the LibDem leader, could be forgiven for being similarly exasperated. As the most, some would say only, admirable LibDem in Cabinet, Mr Cable poses a greater threat to his leader's career than the capitulation over tuition fees.

For those LibDem supporters worried that after the next General Election they will not have enough MPs to form a game of bridge, Mr Cable poses a problem of a different kind. The difficulty is one of timing rather than desirability. In short, should the party that kiboshed Kennedy and muttered Menzies out of a job dump the young pretender Clegg and hope Vince can save them?

Just when you thought Mr Cable's cred on Populism Street could not be any higher he was called a "socialist" by a rich Tory who thinks it wise, at a time of high unemployment, to make it easier for employers to sack people. For his next policy trick, Adrian Beecroft, the venture capitalist commissioned by David Cameron to review employment law, will doubtless be investigating the desirability of putting toddlers up chimneys in a cunning bid to slash childcare costs.

Mr Beecroft was unhappy at his policy being labelled "bonkers" by the Business Secretary. "He is a socialist who found a home in the LibDems," said Mr Beecroft. Of course. What other explanation could there be to object to such a politically suicidal policy? If anything, the Business Secretary did Mr Cameron a favour by saying out loud what wiser heads should have been thinking in private.

But that's Mr Cable, a greater asset to the Coalition than his enemies would ever admit. Imagine, for one distressing moment, that you are a LibDem supporter. Two years ago you were approached by a salesman dealing in souls. Forget all that stuff about being a party of protest and come in to the parlour, said the salesman. Support us and we'll support you on the causes you hold most dear, such as voting reform. The blood was barely dry on the contract before it all began to go wrong. Tuition fees. The alternative vote referendum. Europe.

Yet through it all there has been Vince the Invincible. OK, he didn't manage to make the bankers pay back their bonuses. Nor did he walk out of the Cabinet when red line after red line was crossed. But if there was someone in there holding the torch for LibDem principles the closest thing to such a being was Mr Cable. Even if he didn't always make it clear.

His opposition to Rupert Murdoch's takeover of BSkyB was only made explicit when he was caught in conversation with two reporters posing as constituents. "I have declared war on Mr Murdoch," he gushed, "and I think we're going to win." He was relieved of his responsibilities on the BSkyB bid soon after and the job passed to Jeremy Hunt, the Culture Secretary. That turned out well, didn't it?

While one would like to think it all panned out as Mr Cable planned, not even a former Glasgow councillor, as he is, could be that cute. When the Prime Minister and his deputy come to discuss how best to handle Mr Cable's outbreaks of opposition within Government, they would do well to remember his Glasgow past so as not to underestimate the man.

It was in this dear green place that Mr Cable was the Labour councillor for Maryhill from 1968-74. While messrs Cameron and Clegg were heading for their independent prep schools, Mr Cable was graduating from the school of hard knocks that is Glasgow politics. We made him here, boys, from girders.

Of course, he was also a namby-pamby economics lecturer at Glasgow Yooni at the time, but even that turned out to be handy when it came to predicting the financial meltdown. How they laughed at Cassandra Cable in 2000 when he warned of the dangers of casino banking; how they scoffed when he furrowed his brows about debt levels. No-one was laughing come 2008 and the run on Northern Rock.

Mr Cable's reputation for telling it like it is economically is of incalculable benefit to the Coalition. Labour is woefully discredited on the economy, while the Tories are blundering at best. Only Mr Cable can say: "I told you so". And when he tries to calm fears and put events in perspective, the public is far more willing to listen to him than any of his colleagues.

Should he go from government, it would be devastating to the Coalition's image as the least worst option on the economy. As he said to those two undercover reporters, Mr Cable knows that he has the "nuclear option" of quitting if he feels pushed too far by his Coalition partners. Out of an increasingly unpopular Cabinet, and with the Coalition tottering, he would be in with LibDem supporters looking for someone to lead them into the next General Election. He's even done the job of party leader before, post-Campbell and pre-Clegg, albeit just for a few months.

But should he go? Mr Cable has shown throughout his time in politics that he can do a mean political tango, dipping and swerving and changing direction on a dime like a master. Though his father was a Tory, he chose to join the Labour Party. In the 1970s he was a special adviser to John Smith, Labour's lost king. From Labour he went to the SDP, and the rest is modern British political history.

The Prime Minister and his deputy must be betting that having turned and turned again, Mr Cable will wager he is better off staying put, and it is better off for them that he does so. Better inside the tent and all that. Indeed, if he stays for the duration he might be their greatest electoral asset.

Vince the Invincible once ridiculed Gordon Brown for having gone from being Stalin to Mr Bean. In some ways, clever Mr Cable has travelled in the opposite direction, and it would take a brave premier and his deputy to push him out now. But if he stays the party could well be over for his party. What a bind for such a nifty little mover to be in.