Did key referendum moments matter?

Last year's Scottish independence referendum campaign, as well as the buzz of day-to-day campaigning, was known for a series of key, headline-grabbing events.

But did any of these high-profile, slickly-produced photo calls and big-name speeches have the intended effect - and did they make the slightest bit of difference?

Here's a look at a few of the main ones.

An independent Scotland would have continued to use the pound under a currency union with the remainder of the UK, or so went the Scottish government's argument.

In the wake of the Scottish government's independence White Paper, put out at the end of 2013, UK Chancellor George Osborne made a flying visit north of the border to announce there would be no such deal, declaring: "If Scotland walks away from the UK, it walks away from the UK pound."

Prof John Curtice, of Strathclyde University, said: "The 'No' side was convinced that, because a majority of Scots said they wanted to keep the pound, if they were told they couldn't have it, the uncertainties in their mind that would flow from that would lead them back towards the 'No' side.

"The difficulty they had is that what they were saying to the people of Scotland was, 'vote for us on the grounds that we wish to deny you what you would like to happen if Scotland became independent.'

Prof Curtice said of Mr Osborne: "Unfortunately for him, the opinion polls, which had already began to narrow in the wake of the publication of the White Paper, continued to narrow in the weeks thereafter.

"It is not clear that it had the intended effect."

Edinburgh University's Prof James Mitchell argued the problem may have been the messenger, saying: "To have George Osborne leading on this was probably a big mistake.

"While the argument itself - if it had been articulated by someone else - might have had an impact I think, because of the unpopularity of the Chancellor, it simply didn't have that."

History professor Ewen Cameron, of Edinburgh University, said of the chancellor's declaration: "At the time, I thought, 'wow, that's a huge error on the part of the UK government'.

"But then when Cameron came out immediately after the referendum and talked about English votes for English laws, one could maybe see this was part of a strategy by the UK government to polarise debate."

Opinion polls were everywhere during the campaign and the most memorable one, conducted by YouGov and published in the Sunday Times newspaper, put "Yes" ahead for the first time - just - on 51%.

But Prof Curtice said it provided only part of the picture.

"The YouGov poll caused a great deal of excitement - an excitement that to some some degree ignored the fact that, on the very same day, another opinion poll by Panelbase actually said it was still only 48% for the 'Yes' side," he said.

"The opinion poll that I think made a difference thereafter was a second poll by TNS BMRB that said things were about 50/50."

"It was in the wake of that evidence that moves were made to abandon prime minister's questions, to get virtually the whole of the parliamentary Labour party to come north and parade in Glasgow city centre."

As the polls narrowed in the run up to referendum day, the Better Together parties were getting panicky.

On Tuesday 16 September, two days before voters went to the polls, the three UK party leaders joined forces on the front of a Scottish tabloid newspaper, making a promise to voters to devolve new powers to Holyrood in exchange for a "No" vote.

Former prime minister Gordon Brown was behind the move - seeking to cement the offer by delivering a high-octane speech right at the end of the campaign.

Prof Cameron said: "A cynical interpretation of The Vow was that it was a last-ditch attempt by Unionist politicians to swing the referendum back in their favour - and maybe it did have that effect in the short term - but I think in the longer term its probably caused more problems for the Unionist side than had a positive effect for them."

Prof Curtice said that finally being able to knock together the heads of the three pro-Union party leaders was a key achievement for Mr Brown.

But he added: "It's not clear The Vow made much difference, not least because if you actually looked at the detail of the opinion poll often regarded as being responsible for it - The YouGov poll for the Sunday Times - you can see very clearly from that poll that among those people whose first preference was more devolution - the group to which the Unionists were then trying to appeal - were already between five and six-to-one saying they were going to vote 'No'.

And Prof Mitchell said: "A great deal is claimed about The Vow that it shifted opinion. We've had a look at this and we simply can't find any evidence that it really had that impact."

Even if the impact was small, The Vow still talked about today, as debate over whether the UK government kept its promise rages on.

Prof Mitchell said the referendum campaign, unexpectedly, ended up taking place on different levels.

He said: "There was the high-profile media campaign run by better together and Yes Scotland, with the big names arguing the case for and against independence. Very adversarial. a lot of heat, very little light.

"On the other hand, there was another campaign in our communities and that's the one that certainly took me by surprise.

"Discussions, debates, deliberations, village halls and in work places. I think that was hugely important and, certainly for me, was unexpected."

Prof Curtice added: "Politicians can huff and puff, TV can get excited, but, at the end of the day, voters can perhaps be making up their own minds in their own timescales and not necessarily being influenced by the supposed dramatic events."