The Liberal Democrats always face the tricky problem in election campaigns of how to attack the Tories in the south of England while simultaneously concentrating their fire on Labour in the north and Scotland.
So you've got to stand back and admire the skill of their home affairs spokesman, Chris Huhne, in devising an immigration policy that manages to do exactly that.
In a speech to the liberal thinktank Policy Exchange he pulls off the trick of promising tougher immigration control in London and the south-east and a more liberal policy in the north and Scotland.
As he said: "The Liberal Democrats are the only party offering a hard-headed assessment of the needs of different regions and parts of the economy."
He claims that the Tory policy of an arbitrary national limit would bring the worst of all worlds: "Immigrants would continue to crowd into the most populous parts of the country - making the policy too lax for the south-east of England and too tight for Scotland." Give that man a job in a coalition cabinet!
