Alex Salmond has had his worst week in years. The SNP annual conference revealed a split over continuing membership of Nato. Then he was exposed  for, shall we say, stretching a point to its limits by claiming he had legal approval for insisting that an independent Scotland would smoothly inherit EU membership from the former UK. Small wonder that David Cameron, no mean  connoisseur of omnishambles himself, crowed at PMQs yesterday . Iain McWhirter in the Herald, explains why Salmond's  spinning was bound to fail.  The scene of his pratfall was an interview with fellow Scot Andrew Neil on the BBC's Daily Politics. The First Minister said he had legal advice from the Government's law officers on the question of whether or not Scotland would be granted immediate EU membership after independence. When asked by Mr Neil to produce this, he said he could not disclose the legal advice because, under the ministerial code, governments do not publish advice to ministers. But this week, in Holyrood, the Deputy First Minister revealed there was no such formal legal advice. Mr Salmond insists what he was referring to in the Neil interview was legal advice "in general terms" that was already available in Government documents. And maybe that was what he meant. But why then did he say it couldn't be published? And why did the Government spend a large sum of public money taking the Information Commissioner, Rosemary Agnew, to court to prevent the disclosure of a blank sheet of paper?