Donald Macintyre's Sketch: Governor of the Bank of England takes a paddle in shallows full of killer jellyfish

After a yes vote in September’s referendum the two countries are brought to the brink of the first Anglo-Scottish war for five centuries by a menacing deadlock over whether the pound will survive north of the border. Scotland has seized control of Trident.

Only one man can cut through the horrendously complex negotiating thicket and prevent the impending catastrophe, a man who by good fortune is a native of neither nation, the impossibly dashing Governor of the Bank of England.

It’s perfect for Hollywood! George Clooney is the obvious choice to play Mark Carney in the movie, with the only problem being (apart from needing elocution lessons to perfect those characteristically Canadian dipthongs, in which “about” sounds something like “a boat”) that he isn’t quite as good looking as Carney.

It’s true there was little sign of his pivotal future role in his Edinburgh speech to businessmen. In Britain, Carney is the most famous Canadian economist since Professor Stephen Leacock. And this was more like a lecture than a speech – Leacock without the jokes. Actually there was one – in which he remarked self-deprecatingly that by the end of it we’d understand why Thomas Carlyle called economics “the dismal science”. And we did!

One sensationalist headline – in the Financial Times naturally – had him “wading” into the Scottish referendum debate, Wade? This was more like a gingerly paddle in shallows teeming with killer jellyfish, which come to think of it is not a bad description of current Scottish politics.

To be fair, verbal caution in public comes with the job. This is a man, after all, who can move markets by raising an eyebrow a few millimetres.

So this master of the judicious pause had no difficulty living up to his promise not to give (what we all wanted) “an assessment of whether Scotland will be overall better or worse off under Independence”. There were nevertheless what unionists will regard as clues. The observation that “a durable, successful currency union requires some ceding of national sovereignty”.

That it was “for political theorists” to decide whether the Eurozone would be a “nation state” once everything was done to make it a truly stable currency. That the stable currency unions he cited were mainly the US and Canada, which when we last looked were single, if federal, countries.

One businessman asked him: “When will you next be in Scotland?” Well, he was looking forward to the Commonwealth Games, he said. That’s the trip he makes before rolling up to Holyrood in a heavily armoured convoy some time in 2015 to save the old country from meltdown, of course.