Are Leaders Better Together In Scotland Vote?

The Yes campaign was quick to tweet the message to its 78,000 followers.

"Westminster's three wise men travel north bearing gifts," it said, adding that the gifts consisted of "Private NHS, Trident and governments we didn't vote for".

Meanwhile, "Better Together" which has only 36,000 followers, made no immediate reference on Twitter to the announcement that leaders of the Conservatives, Labour and Liberal Democrats would all be in Scotland on Wednesday in a joint campaign to save the union.

That's how balanced the decision was: The "Yes" campaign publicising the visit (albeit negatively) and the "No" campaign concentrating on other stuff.

"If I thought they were coming by bus - I'd send them the bus fare," said Scotland's First Minister Alex Salmond, who described it as "an indication of the deep panic at the heart of the no campaign".

So are the three leaders "better together" or should the last push of the No campaign have been left to key figures in the Scottish Labour party, which had been the strategy until yesterday?

It feels like they had to do something. You see it on the sports field; a team on a downward turn subs a man or a tennis player attends to his laces to halt the momentum of an opponent's surge.

Gordon Brown has appeared for the No campaign in Scotland

Polls suggest the Yes Campaign is on the charge so No is quickly changing tact. They rolled out Gordon Brown to announce the timetable for greater devolution. The choice of Mr Brown grabbed more attention than if Alistair Darling had done it.

Then David Cameron and Ed Miliband met on Monday and decided they needed to put on a united front rather than play out their scheduled weekly sparring match in the Commons.

The Labour leader told Sky News: "I can't imagine being in Prime Minister's Questions in Westminster when where we should be, and where I'm going to be, is listening and talking to Scottish voters about the huge choice they face."

David Cameron was in agreement.

"I want them to know that the rest of the United Kingdom wants them to stay," he said.

Nick Clegg said: "I'm an English MP from an English constituency and I don't have a vote in the referendum but I care passionately about the outcome because this is a momentous decision which can have consequences which last generations."

They have agreed to risk the disdain of Scottish voters, who have in the past reacted badly to Westminster's flying visits.

It is a peculiar dynamic. Cameron and Miliband's fates are thrown together.

If the No campaign loses, there's a joint responsibility that would threaten both of their positions. Cameron called the referendum and negotiated its terms. He will be blamed for not agreeing to a "Devo-Max" option on the ballot paper.

The Labour party, however, is the key opposition voice in Scotland to the SNP - who they have been losing ground to.

What's more, without Scotland, Labour's seats in Westminster would diminish, making future general elections much harder for them to win.

When I asked Ed Miliband whether he or David Cameron should resign if Scotland votes for independence, he answered: "That doesn't arise. In any case, this is much bigger than any one individual. This is about the future of our country."