When Gordon Brown reshuffled his cabinet last October, something else changed. With little publicity, the prime minister completely changed the personnel, location and operation of his Number 10 machine.

Peter Mandelson’s return to the cabinet inevitably captured the headlines, with the Conservatives convinced the move would backfire. “The prime minister has achieved the impossible,” crowed William Hague, the shadow foreign secretary. “He has made the government even more dysfunctional.”