The Darien Scheme was an attempt by some Scots nobles to emulate the imperial success of the Company of England by forming a Company of Scotland to found a colony. The colony at Darien failed disastrously because it was in the wrong place (the area is still a lethal hellhole of tropical diseases) and because England was furious at the Scots' uppitiness and refused to aid the colonists when pleas were sent to the Crown.
Then rather conveniently the Scots nobles were bailed out by England in return for their country and the dissolution of the Scots parliament. Unsurprisingly this was not popular, it was basically a treasonous act for financial gain. "We have catch'd Scotland and would keep her fast," chortled the Speaker of the English House of Commons in 1708.
That base political instinct has not changed much since then.
To assert that Scotland today is too wee and too poor to be independent is not a view supported by most economists. We do not need all the expensive things that proponents of the UK seem to think essential: the nukes, the spies, the fourth largest defence budget in the world.
If Norway is the current model for the SNP, that seems reasonable to me as a starting point. Independence is not necessarily just about the SNP's vision though. To paraphrase, "another Scotland is possible".
A no vote is not a vote for the status quo. Things will not be the same afterwards either. It's easy to forget what happened after the rigged yes vote in 1979 failed to bring about a Scottish parliament. I remember very well what the Conservatives under Thatcher wreaked in Scotland during the 1980s. The 'permanent austerity' ideology revealed by Osborne recently shows what is in store for us after a no vote.
As for Carney's statement, he was candid, yes. He was also clear what lay in the domain of political decisions and what the role of a central bank would be. He chooses to forget that his home country of Canada has the Quebecois independence movement. If at some future point Quebec becomes independent, does anyone seriously suggest Quebec would not use the $Canadian as currency? Similarly it is ludicrous fear mongering to suggest, as Bitter Together are doing* that Scotland would be forced out of the pound zone upon independence**. At some future point Scotland might require its own currency: that may not be a bad thing at all. I don't see being out of the euro zone hampering Norway, Sweden or Denmark. As a transitional arrangement though, using the pound seems common sense, just as newly independent Ireland did in the 1920s.
* - I was flyered by one of their activists to this effect at the entrance to Waverley station yesterday.
** - This position sees an independent Scotland as a 'new' entity, therefore our use of the pound, membership of EU, NATO, UN, etc. are all void. The alternative position (put forward by the SNP amongst others) is that Scotland's status would be that of a joint successor state of the no longer extant UK and would have a stake in all the assets and liabilities of the defunct former UK. The naysayers' independence scenario, if it came to pass, would of course also liberate Scotland from the huge UK state debt.