The other week it was George Osborne, claiming that Scots would need to smuggle pounds into the country, as if money could only exist if it’s printed or minted. In March Theresa May was suggesting that if Scotland has a different immigration policy from England they will have to show their passports at the border, a position that muddles border control with immigration control. Yesterday David Cameron suggested that it Scotland wanted to join the EU it would have to join a queue behind Serbia and Montenegro, misunderstanding why the entry of those countries has been delayed – Scotland, unlike other candidate countries, already has laws and procedures that are fully in conformity with the acquis communautaire. We might explain this flurry of daft comments as evidence of animosity towards Scotland. Possibly the ministers are playing the sort of game that politicians enjoy, seeing who can slip in a previously agreed phrase and win the cabinet sweepstake. The content might be taken to indicate that our senior politicians don’t much know what they’re talking about. But I suspect the hand of campaign adviser Lynton Crosby, who thinks the way to win politically is by keeping up a constant barrage, regardless of the merits of the arguments.