A small cottage stands in the grounds of Premier House, the Prime Minister's Wellington residence.

It is the door John Key would knock on if he ever ran out of sugar, or desperately needed milk for his tea.

So it was apt the cottage's keys went straight to his trusted lieutenant Steven Joyce in the divvy-up of ministerial housing, giving him the same digs as Jim Bolger's right hand man, Bill Birch.

Joyce is the man Key turns to for much more than milk and sugar; he's the go-to guy for advice on running the entire show. When Key gets back to work next week, he will count on Joyce's assessment of what went down in his two weeks away.

That will obviously include the Bill English housing saga. Joyce is virtually unknown to the public, but his standing is so high within the party that before English took the heat out of the issue on Monday Joyce was the obvious successor in the finance role if change were needed.

After being ushered in off the street into a top Cabinet role, Joyce's strategy role makes him one of the Government's most powerful ministers - with some strikingly similar characteristics to Key.

He has done in an instant what some MPs fail to do in their entire career, making it look all too easy with an accomplished performance in the House and with his portfolios.

Joyce's transition this year from ordinary citizen to parliamentarian and his influential role make more sense when his backroom role with National in recent years is taken into account.

He was the "retired" multi-millionaire media mogul to whom the party turned after its disastrous 2002 election result. As its general manager he reviewed, reorganised and refocused it enough to get Don Brash within a whisker of victory in 2005.

He has been demonised as a Hollow Man for approving the Iwi/Kiwi billboards and dealing with the Brethren. But the turnaround result means no matter what Labour says about him in public it must fear and respect him as a political operator.

Joyce took up a tactical role in Key's office when he took over as Opposition leader, gaining critical experience in watching Parliament and learning how ministers should (and more importantly should not) act, and was campaign manager in last year's election.

His seamless move into Parliament may be unparalleled. It surpasses Margaret Wilson, who was similarly parachuted into the Cabinet for Labour and while also steeped in party politics was not a particularly comfortable fit with parliamentary politics.

He has already ridden out his novice stage in the House, rarely being riled by his far more experienced Labour opposite in transport, high-flyer Darren Hughes.