It started on a positive note ... and ended in a torrent of recrimination barely hours after the polls closed

"Some of their people were refusing to canvas. They didn't want to go out. Unbelievable."

Labour had been terrible from the start, the key Better Together member continued. Alistair Darling, Better Together's chairman, had been "weak", insisting on a "no firing policy" that burdened the operation with poorly performing staff.

Not even a senior aide who was thrown out of a LibDem conference for drunkenly calling activists "c***s" could be ousted.

Labour's data was terrible, they hadn't canvassed their own areas in years, they didn't know where their people were, they refused to share what data they had with other parties.

On and on went the diatribe, as the tension of the past two-and-a-half years finally found a release in the early hours of Friday morning.

It was a vivid sign of the dysfunction that almost saw Better Together lose on Thursday and a reminder that, in many ways, No won in spite of, not because of, its campaign.

It may be hard to believe now, but Better Together started on a positive note. Its first press release, issued before its launch at Edinburgh's Napier University on June 25, 2012, declared: "Alistair Darling to make positive case for ­staying in the UK."

The former chancellor called Scotland a "proud nation", united with the rest of the UK by friendship and family, as well as the economy.

The truth, he said, was that Scotland could have "the best of both worlds", and that the Union was "an ideal worth celebrating".

It was an optimistic message that seems almost alien compared to what Better Together became.

But tucked away at the foot of that same notice was a clue to its future direction.

Darling would add: "The choice we make will be irrevocable. If we decide to leave the United Kingdom there is no way back. It is like asking us to buy a one-way ticket to send our children to a deeply uncertain destination."

So positivity was not the only Better Together approach - it was happy trading on fear too.

It had a choice over which to pursue the ­hardest, and which to keep in reserve.

It decided, at Labour's urging, to go negative.

"Because negative campaigning works," said a source in the campaign. "People might not like it, but it works, and the focus groups suggested people were worried about independence."

The strategy guaranteed Better Together lurid headlines but in the long term it was a trap.

The No campaign became so obsessed with raising concerns about independence it stopped saying anything positive about the Union until it was forced to by a late lurch in the polls.

There were other strategic blunders.

From the outset, Better Together's aim focused exclusively on undecided voters.

It estimated there were a million of them, and swaying the bulk would guarantee a No vote.

To all intents and purposes, that meant all other voters were simply ignored.

This was a potential strength, as resources could be applied to a key demographic without wasting or duplicating effort.

But while Better Together was tailoring its script to the undecided, Yes Scotland was working to capture every vote it possibly could, including those assumed to be in the No camp.

Better Together, therefore, needed its voters to stay faithful for more than two-and-a-half years, to withstand Yes's relentless sales pitch, and to resist any shift in the national mood.

It needed them, in other words, not to act like people at all, but to behave like drones.

In the end, Better Together found many of those it took for granted had their own ideas about September 18, and switched to Yes.

Critically, Labour voters became part of that unforeseen movement, with one poll suggesting 37% of Labour voters backed independence.

The UK Government made an equally bad decision.

Like Better Together, it believed voters would put their heads before their hearts and vote on the basis of personal economic wellbeing.

It therefore embarked on one of history's least successful publishing enterprises.

The "Scotland Analysis" papers were intended to put some intellectual heft into the case for the Union, to demonstrate scientifically, table by table, graph by graph, the uncertainties and pitfalls associated with independence.

Started in February 2013, by June 2014 it had grown to more than 1200 pages in 15 volumes of indigestible voter-repellent.

As a campaigning tool it was utterly useless.

"Campaign in poetry, govern in prose," the New York governor Mario Cuomo once said.

The No side was trying to campaign in statistics.

Better Together's other fundamental campaigning weakness was its lack of personality, something in which it took a perverse pride.

Blair McDougall, the Labour Party apparatchik appointed as its director, wanted a robotically efficient, vote-harvesting machine.

"We don't care if no-one knows we're called Better Together, because we're not going to exist the day after [the referendum]," he said earlier this year.

In contrast, Yes Scotland created a movement.

With too few voters to deliver a Yes, the SNP forged a rainbow alliance with socialists, Greens and the non-aligned and spent £170,000 dressing up a walk-in office on Glasgow's Hope Street for curious passers-by.

Better Together, meanwhile, retreated to an anonymous garret on Blythswood Square, from which the general public were excluded.

Even in the latter stages of the campaign, when Better Together established a second office on Sauchiehall Street, it was characteristically hidden from sight.

Anyone who made it to the fourth floor of the Savoy Centre found scattered desks and stressed staff amid random boxes of campaign materials. One campaigner said it looked "like Lidl".

This was because McDougall saw Better Together as purely functional - its job was to win. A personality, like a welcoming office, was an unnecessary adornment. But the cult of anonymity came to haunt Better Together.

Because it lacked any identity of its own, its opponents saw they could superimpose one.

All they needed was a catchy name. It arrived via the Scottish Conservatives' conference in June 2013.

The event became famous at the time for Darling getting a standing ovation from Tory activists.

Few can now remember what Darling said. But as one of his aides was drinking later, he let slip a phrase no-one would forget.

"Project Fear" was Better Together's private pet name for itself, an office joke lampooning what it regarded as Yes Scotland's hysterical view of everything said by the No camp.

When the Sunday Herald reported it, it was picked up on by social media and took on a whole new dimension. It was the stick Yes Scotland had been looking for, and they deployed it with relish.

It seemed to sum up everything Better Together was doing wrong - the one-dimensional approach, the hectoring, the negativity, the coldness.

As the campaign wore on, tensions emerged. Last September, ex-LibDem leader Tavish Scott wrote a newspaper article decrying Labour's weak effort and premature triumphalism.

"Labour need to get their act together on the referendum. There needs to be a consistent message ... No vote can be taken for granted."

The frostiness between the three partners continued through the winter.

In December, Tory MPs began briefing against Darling, calling him "useless and comatose".

They correctly saw that Better Together had "no fire in its belly" and was drifting to failure.

The spring brought worse.

In February, after months of preparation, the No camp played what it thought would be its trump card: the announcement that Alex Salmond could not have his plan of a formal currency union.

With focus groups highlighting the currency and the economy as a key concern, Better Together thought it would seal the deal for a No vote.

But how the message was delivered - on a flying visit to Edinburgh by the Conservative Chancellor George Osborne - backfired horribly.

One campaign insider said Osborne's statement was expected to generate a small backlash, but Better Together was unprepared for the reality.

Alex Salmond and Yes Scotland played a blinder by turning the event on its head.

Instead of being a demonstration of Salmond's wishful thinking about the pound, the statement came to symbolise Westminster arrogance towards Scotland - and cemented many of the Yes side's key campaign messages.

Osborne's visit helped sell the idea that it was Scotland's pound as much as the UK's, and that a Yes vote would end Tory rule in Scotland and put Scotland's future in Scotland's hands.

A month later there was more friction.

The LibDem conference in Aberdeen began with a series of MSPs taking swipes at Labour.

Tavish Scott ramped up his previous attack with a call for Labour to put forward its star names and said he was not sure what Better Together's response was to the gathering momentum for Yes.

The LibDem revolt against Labour was becoming the story of the conference until it was overshadowed by a bombshell report in The Guardian that an unnamed Coalition minister had said "of course" there would be a currency union with an independent Scotland, possibly in return for maintaining Trident at Faslane.

LibDem Scottish Secretary Alistair Carmichael raged that he wanted to "castrate" the leaker.

Then Scott got his wish for Labour's big beasts to chip in - but not the way he hoped.

In June, Gordon Brown, who had been largely absent from the campaign, dramatically intervened to badmouth Better Together tactics.

He warned that "threats and ultimatums" risked alienating voters, and accused the UK government of being "patronising".

He also, to David Cameron's anger, suggested it would be a "good idea" if the Prime Minister agreed to a TV debate with Salmond.

It seemed like the No camp was in disarray.

Around the same time, the three parties published their conflicting plans for more powers for Holyrood in the event of a No.

This was meant to offer reform to voters who wanted more than the status quo, but merely fed into the narrative that Better Together was divided and lacked a coherent plan.

Of course, it wasn't all calamity.

Better Together did a lot right as well.

Its strategy may have been imperfect, but Better Together nevertheless showed discipline in sticking to it, continuing to push the same key messages that resonated with focus groups.

Refusing to be deflected by Yes claims of scaremongering, they continued to plug away on the themes of uncertainty and risk and the pound, even after Darling spectacularly lost the second TV debate with Salmond.

Better Together also hit back hard and fast when the Yes campaign started a deeply cynical and dishonest scare story of its own about a No vote leading to NHS privatisation in Scotland.

That, said Better Together, was a flat "lie". In the closing stages, Better Together finally hit its stride. A YouGov poll putting Yes ahead for the first time shook Westminster out of its complacency. Cameron, Nick Clegg and Ed Miliband came north to plead with the Scots not to end the UK.

A transformed Gordon Brown re-entered the campaign, giving a series of fiery speeches that brought wavering Labour voters back to the fold, and provided some passion for the Union.

He may have been late, he may have been partly doing it to upstage his old rival Darling, but it worked, and boosted the No camp's morale.

Downing Street also stepped on the gas at the right moment, urging banks and businesses to air their concerns about independence.

In the penultimate week of the campaign the Yes side was subjected to the political equivalent of carpet bombing, as waves of companies talked of relocating or raising prices after a Yes.

The barrage hit home with the undecided voters who Better Together had already targeted with warnings of economic risks.

Then, at the insistence of Scots LibDem leader Willie Rennie, the three parties agreed to sign a "vow" on more powers for Holyrood.

It wasn't pretty - "Our aim was always to be good, rather than look good," as McDougall said yesterday - but it was effective.

In response, Salmond turned to stories about rows with the BBC and the Treasury, which did nothing to reassure waverers.

The Yes campaign's attempt to create a carnival atmosphere on the streets of Scotland was also no answer to genuine voter concerns.

Behind the scenes, Better Together grew increasingly confident of winning.

It may not have had the colour or noise of Yes Scotland, but it was phone-canvassing hard, and the results showed No was safely in the lead.

Strategists suspected the Yes campaign was falling victim to its own hype, with novice canvassers over-estimating the true level of public support for a Yes vote and feeding back inaccurate data to Yes Scotland HQ.

That suspicion was borne out on September 18.

As the polls closed, Labour confidently predicted a 55% win for No - bang on the money.

Meanwhile, insiders at Yes Scotland were consistently off the mark, projecting a 90% turnout in Glasgow (it was 75%), a 71% win in Dundee (it was 57%) and an overall Yes vote in Highland Council (No won with 53%).

Now comes the aftermath.

As the national count wound down at the Ingliston showground near Edinburgh, Richard Keen, the chairman of the Scottish Tories, made it clear it was Better Together no more.

Like many unionists there, he had been struck by the scale of the No turnout in strong Conservative areas such as Dumfries & Galloway and the Scottish Borders, where No was above 60%, and the failure of Labour to deliver comparable results in its traditional areas.

The Tory vote anchored the No result across the country, remaining rock solid, while the former Labour heartlands of Dundee, Glasgow, North Lanarkshire and West Dunbartonshire voted Yes.

"What now for the Labour party?", Keen grinned, referring to this ill omen for Labour ahead of the 2015 and 2016 UK and Scottish elections.

Once the referendum was over, traditional party loyalties were always bound to re-emerge.

However, the strong Tory and LibDem sense that held up their end in the referendum, while Labour failed on the basics, has left particularly bitter feelings in the No camp.

Those feelings will inevitably colour the talks between the parties at Westminster as they try to legislate on new powers for Holyrood.

There is the potential for in-fighting to bring the new powers programme to a juddering halt.

The Unionist parties may have won the war, but they may yet lose the peace.