So exactly what would be on the negotiating table from the UK Government's perspective in the event of a Yes vote in the referendum?

First the Prime Minister David Cameron said that there would be no "pre-negotiation" - no advance discussion of what a post-Yes independence settlement might look like. Then the Chancellor George Osborne departed from that position by ruling out a currency union with an independent Scotland, a stance backed by the Labour Party and the Liberal Democrats.

Then an unnamed UK Government minister suggested that actually, Scotland could share the pound, in return for Trident staying on the Clyde. Although that comment was condemned as nonsense by the Lib Dem chief secretary to the Treasury Danny Alexander, now the Defence Secretary Philip Hammond has made the observation that "everything will be on the table". Mr Hammond was himself correcting the assertion of Scotland Office minister David Mundell who last week stated that the SNP's position on removing Trident could not be negotiated; the defence secretary was insisting that view was wrong. But his stance will be trumpeted by pro-independence supporters as proof that the Government does not really mean it when it says over currency union.

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The sight of Coalition ministers tying themselves in knots by repeatedly contradicting each other will infuriate pro-UK supporters. There is likely to be some fruity Scots vocabulary used about Mr Hammond this morning. But he is right to suggest that everything should be up for negotiation. If one side has issues on which they are not prepared to be flexible, he notes, "invariably you have to give way on other things in order to achieve your objectives". That is common sense. With so many big ticket items to be discussed, it would make little sense to start with a closed book on any issue.

But does this really count as proof that the UK Government will simply concede to a currency union? No. Each side has clearly drawn unambiguous lines in the sand. For the UK Government, there are serious downsides to a currency union as it would require close alignment between the two nations on tax and spending policy which the Scottish Government would be unlikely to accept; ministers are not bluffing about that, any more than the Scottish Government is bluffing over its determination to see Trident swiftly removed from Scotland.

Meanwhile, Mr Hammond has a point with his assertion that Alex Salmond's proposed independence date of March 24 2016 is arbitrary. It is not arbitrary for Mr Salmond, of course - it falls just before the Scottish parliament elections of 2016 - but the SNP's electoral ambitions should not dictate the timetable for independence negotiations when it could be against Scotland's interests to shoehorn any talks after a Yes vote into that time frame.

Voters want clarity, but with one side making dubious assertions, and leading figures on the other contradicting one other, they are likely to be more confused than ever.