ONLY nine per cent of Scots believes that “The Vow” has been kept, according to a new poll. The Vow, signed by Prime Minister David Cameron, then Labour leader Ed Miliband and then Liberal Democrat leader Nick Clegg promised Scots more powers if they voted No in the independence referendum.

The Vow appeared on the front page of the Daily Record newspaper exactly a year ago today. It was one of the most important media interventions in the whole campaign.

Yesterday, as a YouGov poll revealed that voters in Scotland roundly dismiss claims that The Vow has been fulfilled, details of how it came about were revealed in a sensational new book looking behind the scenes of the Better Together campaign. Joe Pike’s Project Fear, out on Friday, features incredibly candid interviews with many involved in the No campaign.

The Vow was conceived and drafted by journalists at the Daily Record, in consultation with former prime minister Gordon Brown.

The three party leaders signed up with the idea after a poll put the Yes campaign ahead for the first time in two-and-half years.

According to the book, Brown was first approached by the Record on the afternoon of September 11.

The Daily Record had contacted the former prime minister after Ed Miliband had brought 104 MPs to Glasgow. Their slow march down Buchanan Street became a PR disaster. It was soundtracked by protester, Empire Biscuits, playing the Imperial March from Star Wars through a giant PA and using a megaphone to shout, “Say hello to your imperial masters ... People of Glasgow, your imperial masters have arrived!”

That afternoon the editor of the Record contacted Brown to ask if he could get Miliband, Clegg, and Cameron “to sign an agreed Daily Record pledge for more devolved powers (subject to a consultation process as per Gordon’s timetable)?”

Printed on the 16th, The Vow became an important part of the constitutional debate before and after the referendum.

So important was The Vow to the Smith Commission, according to the book, that civil servants responsible for keeping the commission on track had copies of the Daily Record’s front page plastered over their wall and would often ask of proposed policy “Does this fit with the framework of “The Vow”?”

The book comments that this “hastily arranged front page” has become “central to the changing constitutional position of the UK”.

Yet, in the poll, released yesterday, 52 per cent of those replying believe “very little” or “nothing” has been delivered of The Vow.

Commenting, SNP MSP Linda Fabiani said: “This poll is a damning indictment of the UK Government’s broken promises on further devolution.”

She continued: “The cross-party Devolution Committee recommended serious amendments to ensure the Bill meets the Smith Commission – these have been ignored by the Scottish Secretary.

“The SNP’s 56 MPs, with an unprecedented democratic mandate, put forward amendments to strengthen the Bill – these were all voted down by Tory MPs.

“David Mundell needs to start listening to Scotland and amend the Bill – the level of disappointment in the current offer could not be clearer.”

Other revelations in Pike’s book include the resentment towards Rob Shorthouse, Better Together’s communications director, who was paid an annual salary of £100,000 rising to £105,000, significantly more than Better Together chief Blair McDougall.

The campaign also spent £50,000 on an advert that was never shown, nicknamed ‘Nightmare on Sauchiehall Street’.

And with £27,000 was spent on the overnight results party on the 18th, the campaign ended up being £200,000 in debt.

More revelations from Project Fear in Friday’s paper.