Is devolution good for independence? Alex Salmond cites a YouGov poll, published yesterday, as evidence that being a major player in the Scottish Parliament, to the extent of the SNP managing to form a minority administration at Holyrood one year ago, has been positive for the SNP. The poll findings confirm there is some cause for the First Minister's optimism.

Mr Salmond's personal approval ratings leave him in a league of his own compared with the leaders of the other parties in Scotland who are not within touching distance of his popularity. Significantly more respondents say they would vote for the SNP than in 2007 (the last Holyrood election) and 2005 (the previous Westminster poll).

The contrast between Mr Salmond's standing and that of Gordon Brown, his fellow Scot, is stark. The poll suggests that mud has not stuck and that, despite problems for the First Minister over the Trump planning application and a disappointing lack of delivery on key manifesto pledges, notably in education, the honeymoon is not over.

But Mr Salmond would be unwise to bask in contentment. The poll also points to devolution being bad for the cause of independence. Only one respondent in four supports independence, falling to fewer than one in five when an option to vote on Holyrood securing more powers is added. The paradox of Scottish politics - an SNP administration, popular on many measures, failing to make any progress on its core policy of independence - has become more, not less, prominent on the landscape. Of course, politics is a long game and Mr Salmond will hope that winning public confidence on the back of competence in government will eventually secure the ultimate goal.

There are risks in this for the First Minister, not the least of which is these figures being exploited by those Nationalists who believe devolution is a trap and that being sucked into it will bring its own punishment for their party. In other words, there is a comfort zone (the Union) that people are reluctant to leave when they have a popular, charismatic leader pursuing populist policies within a constitutional framework that has stood the test for 300 years.

There is some truth in this analysis but what could be bad for the SNP, in terms of the prospects for its founding policy, is not necessarily bad for the public, in terms of Scotland's adminstration. There is scope to build on the desire for Holyrood acquiring more powers, in a responsible way. Mr Salmond has raised the possibility of a multi-option referendum on Scotland's future, to include the status quo or more powers for the parliament as well as independence. On these figures, he would be hard pressed to win the independence argument. Although the poll does not specifically mention local income tax, the facts that only 16% of respondents support raising the basic rate of income tax, while 61% are against, must be ominous for winning popular approval for a tax to replace council tax that would be centrally-set. On key policies, such as local income tax, Mr Salmond still has not convinced.