OK, so according to the Canadian story (see here), in order to grip the beast, Cam is going to need a Minister
He's going to need someone who can lead a calm rational "egos left at the door" discussion among spending ministers.
Someone who can deliver rapid and substantial spending cuts, not by destroying the public services, but by reinventing the very role of government.
Someone who's been round the fiscal loops a few times, but who is not part the Treasury team.
Someone who can command respect, but who can knock heads together if the need arises.