Doctor Alison Elliot is still undecided but said David Cameron, Ed Miliband and Nick Clegg coming north of the border was unlikely to change anyone's mind.
Doctor Alison Elliot
She's now an Associate Director at Edinburgh University's Centre for Theology and Public Issues and said: "David Cameron is himself saying that he knows he's not popular in Scotland.
"The thing which makes the whole thing so tense is that you're conscious that people can put their foot in it very, very easily.
"If people are on a knife edge in terms of the way they're going to vote then the slightest little thing can switch them into deciding whether they trust them or not and therefore that can have an effect on the way in which they vote."
Scots will be asked the yes/no question 'should Scotland be an independent country?' on 18 September.
Meanwhile the Prime Minister says he cares more about the UK staying together than he does the Conservative Party.
In Edinburgh David Cameron said he hopes Scots decide to vote 'no': "I care hugely about this extraordinary country, this United Kingdom that we've built together.
"I would be heartbroken if this family of nations that we've put together - and we've done such amazing things together - if this family of nations was torn apart," he said.
But Dr Elliot added it may have taken too long for the Prime Minister to offer the strong words.
She said: "It's taken a long time for Westminster politicians to recognise that and be seen to be taking this campaign seriously."
The polls have been narrowing recently and a You-Gov survey at the weekend gave the Yes campaign the lead for the first time.
David Cameron warned the referendum was not about the Conservative party.
"Because it is an election people think it's like a general election.
"If you are fed up with the Tories give them a kick.
"This is not a decision about the next five years, but the next century," he said.
Elsewhere Scotland's First Minister Alex Salmond said the campaign was now Team Scotland against Team Westminster.
He said: ''The breadth and reach of the Yes campaign is there for all to see, it's not about the Scottish National Party, the Green Party, it goes right through every sector of Scottish society.
''What we're seeing today on the other side is Team Westminster jetting up to Scotland for the day because they are panicking in the campaign.
''We don't make any assumptions about the poll next week but nonetheless the evidence would indicate that more and more of our fellow citizens are becoming convinced by the arguments being put forward by their fellow citizens in the Yes campaign.
''The movement in Scotland is decisively towards Yes.''
Speaking about the three leaders deciding to visit Scotland Mr Salmond said: "The message of this extraordinary, last-minute reaction is that the Westminster elite are in a state of absolute panic as the ground in Scotland shifts under their feet.
"The No campaign is in complete and utter disarray, and they are making this farce up as they go along.
"Together, David Cameron, Ed Miliband and Nick Clegg are the most distrusted Westminster politicians ever - and their collective presence in Scotland will be another massive boost for the Yes campaign."
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