Since Johann Lamont unveiled Labour's plans for further devolution, the referendum arguments can no longer be reduced to change versus the status quo.

Even Nicola Sturgeon, the Deputy First Minister, accepts the commitment of all parties to bring more powers to the Scottish Parliament.

What was less appealing in her response, and for which she has no evidence, is her claim that "there is no guarantee that any new powers would be delivered in the event of a No vote." Ms Sturgeon is wrong, not just because Labour has shown its hand. We know the Liberal Democrats have more ambitious tax plans than Labour and, although the Tories' Strathclyde Commission is not due to report until the end of May, it is "not inconceivable" that they too will go further. At this stage it might be a good idea for the nationalists to reveal what tax regime they favour if Scottish voters elect to stay in the UK.

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The evolution of policy in the Labour and LibDem parties, and the Tory volte face, chime with the views of a majority of Scots who believe their economy, social policies and creativity will flourish if they have greater autonomy and greater financial and legal powers.

A large trenche of Labour MPs opposed the devolution of further powers but they have signed up and, given the chance, will deliver the policy. That is how party manifestos emerge. The commitment is no weaker because it had to fought for.

The more dramatic and fundamental Tory change should not be a surprise. Younger, modernising grassroot Tories, desperate to reclaim once true-blue Tory territory in a Scotland sending SNP MPs to London, found David Cameron's door was open.

The old guard didn't much like the Prime Minister saying that "a true Conservative should be giving people more control over their own lives" only days after Lady Thatcher's death. But close colleagues believe his commitment to devolving more authority to local government and cities, as well as the Welsh and Scottish parliaments, is a key plank of his political agenda.

The naysayers will dismiss the devolution commitments much as they dismissed the parties' commitment to refuse Scotland a currency union with the rest of the UK.

If George Osborne, Ed Balls and Danny Alexander say they will not sign up to a currency union who are we to say they will? Senior politicians don't march their foot soldiers up to the top of the hill to march them down again on issues as important as the currency. As well as considering the UK's internal market, any Government has to maintain credibility with international creditors.

From the nationalists' point of view, the best they can hope for is to join a currency union. They cannot be certain. Uncertainty is as applicable to Scotland's membership of the EU. I don't know if Scotland, having broken away from the rest of the UK, would still be welcome in the EU and neither does anyone else. Anyone with experience of EU negotiations knows a line in a communique can take days if not weeks to complete. The exit and re-entry of another country is likely to take years.

Professor John Curtice, consultant to the survey of Scottish social attitudes, says voters want to hear about the economic and financial consequences of the choice they make and it is on the outcome of that debate that the result of the referendum is likely to turn. The only certainty in that debate is that the future is uncertain.

For the sake of clarity, I know of no-one who thinks Scotland would not survive if it left the UK. England and Wales would survive, too, but each country would be diminished. Voting power on the European Council, for example, is based on a country's population and the UK has votes equal to Germany, France and Italy. If Scotland breaks away, the UK might drop a vote but Scotland, if it was allowed to sit at the table, would be nearer the bottom alongside Denmark and Croatia.

All parts of the UK have benefited from being together, not least in Europe. Further devolved powers are on the way whichever party wins the General Election. Let's focus on how the politicians want to use their new powers rather than dwell on constitutional upheaval.