YES was at 51% in a poll and a jubilant, confident Nicola Sturgeon could not have been happier.

“Scots,” she declared, “want a real parliament that can effect positive change on their lives, their families and our communities, not one stuck in the past, wed to remote control from London.”

The survey, published in The Scotsman, suggested she had a point. Independence was not just leading union, it had opened a 12-point gap. No was lumbering at 39%. Nervous unionists played down the numbers. Sturgeon and her buoyant SNP vowed to redouble their efforts: victory, they must have hoped, was in sight.

Does this sound familiar? Was this poll conducted while the first minister was riding high at the height of the pandemic? Or in the heady months after a largely English vote took Scotland out of the EU against its will?

No, the 51% Yes figure was from November 2006, six months before Ms Sturgeon and Alex Salmond, her then leader and now nemesis, secured a historic first Holyrood victory for the SNP. Take away the “don’t knows” and support for independence 15 years ago was close to some of the record highs recorded last year. And way, way above the scores recorded over this summer as No slowly nosed back ahead.

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The polls, they go up; and they go down. The only thing in Scotland’s sometimes feverishly stupid tribal politics that stays the same is just how bad the patter about each survey can be.

Last year SNP politicians – as happy with the polling of 2020 as Ms Sturgeon was in 2006 – started tweeting about Scotland’s “settled will”.

This summer unionists, enjoying a wee dig, said the same thing. But zooming out, looking at the jagged lines of opinion polls over years and decades, it is quite clear that Scotland’s will is far from settled. We are a society divided on a single, simple wedge issue. We have a disagreement to manage. So far we have done so without gouging each other’s eyes out. Except maybe virtually.

Polls are one of the things very online tribalists like to squabble about, like football fans one-upping each other about meaningless pre-season friendlies. Some – bluntly – have zombified their brains in the process.

Hyper-partisans on both sides fret over how to spin any setback, including abusing journalists who cover any survey and defaming news organisations which commission them.

More passionate independence supporters, falling in to teleological reasoning, can feel the need to portray numbers as showing progress to their goal. So events, such as the discovery of oil, the Thatcher recession, the War in Iraq, the financial crash, Brexit or the pandemic are just milestones on a one-way highway to a sovereign state.

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Their unionist opponents prefer to see independence as impossible, that they are the natural majority, the pro-UK mean to which Scotland will always regress. Meanwhile, history rumbles on.

Political movements like to move, they like momentum.

That is why that historic 2006 poll, or any of the other high Yes numbers in the 1990s and early 2000s, are not helpful to the “national cause”. If you start your comparison from just before the SNP came to power, it looks like they have lost ground for their core political objective over the 14 years they have governed Scotland.

Is that fair? I don’t think so. Support for independence collapsed during the financial crisis of 2008 even as then-first minister Salmond was in his ebullient pomp as the leader of a minority administration. “Events, dear boy, events,” as Harold Macmillan said.

In fact, polling for independence has swung back and forth several times during the SNP’s reign.

After the 2014 referendum some nationalists consoled themselves by resetting the clock, forgetting the highs of early this century.

Their campaign, some Yessers told themselves, was a success because the SNP and the wider national movement pushed support for Yes from an low of under 30% in 2011 to 45% in 2014.

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I can remember journalists who reported poor scores for independence in 2011 being slated online for doing so. Now these same numbers are seized upon by the most impatient independence supporters to support two narratives.

The first is that all they need is a referendum and one final push and they will deliver Yes.

The second is that Mr Salmond, now a Putin TV personality, did more to progress independence than Ms Sturgeon.

Both these ideas seem wonky to me. First, because picking two random points in a moving series of poll numbers is not particularly illuminating. And second, because they assume that it is just politicians who move polls.

Mark McGeoghegan is a polling expert and a doctoral researcher at Glasgow University looking at independence movements around the world.

He stressed the importance of events – and the sheer salience of the issue – in shaping attitudes to leaving the UK.

Unionists, he said, back in 2014 had done just enough to shore up risk-averse, middle-class Scots with a high propensity to vote. But there are also times when such voters will flirt with the idea of independence. During the pandemic, for example.

“There are people out there who vote with their heads over the hearts, who like the idea of indy but it’s never the right time,” he said. “When everything was going to hell in a handcart some of them were asking themselves: ‘how much worse can it be if we were independent?’”

Worrying about every poll will blow your mind. Fixating on every up and down trend will do the same. Nobody knows where those two lines, Yes and No, will now go on their graph.

But we do know where they started. From the late 1970s until the mid 1990s, before the Scottish Parliament reopened, Mori fairly regularly asked Scots if they would prefer independence, devolution or the then status quo of direct rule.

The numbers bobbled about. Devolution, broadly speaking, was preferred by about half of all those asked. Independence was usually polling somewhere between a quarter and a third, sometimes a little more. But never anywhere like as high as the peaks we have experienced in the 21st century. Change, sometimes at least, can take generations.

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