I’ve always liked the way Singapore’s autocratic government cycled through Prime Ministers but kept a spot for Lee Kuan Yew, who first was “Senior Minister” for Goh Chok Tong and then, when the latter was elevated to that position because it was Lee’s son’s turn to be Prime Minister, became “Minister Mentor”.

Doubtless that sort of altruistic thinking is behind Peter Costello’s evident decision to become Senior Shadow Treasurer, an informal advisory role to the actual Shadow Treasurer, Joe Hockey, whom Costello was careful to point out yesterday had been his “junior minister” when they were in Government — just in case anyone was under a misapprehension about who was more important.

During Question Time, Hockey is often to be seen — when not howling “what?!” incredulously at every statement from the Government — having a chat with Costello, so undoubtedly that will only increase in frequency now that Joe has the big gig.

Costello wasn’t waiting around for Joe to get up to speed on the Rio Tinto-Chinalco deal, however. He showed the new lad how it was to be done this morning in the SMH, holding up his own foreign investment decision on BHP-Billiton as the model to follow.

I was hoping, as I read through it, that he’d also talk about what a great decision his approval of the Qantas takeover in 2007 would have been now if fate hadn’t cruelled that particular deal for Mac Bank. No such luck.

Joe might want to be careful of Costello’s advice because something tells me it’s not entirely disinterested. In fact, Costello is having the time of his life messing with the rest of his party. Last year he did it by not opening his mouth for long periods. Now he won’t shut up and it’s causing even more damage.

By the time all this is finished, boy are they going to be sorry they never gave him the Prime Ministership. And Turnbull is going to regret embarrassing Costello with his tax plans when he first arrived in Parliament. The current Turnbull-Costello relationship makes the Howard-Peacock rivalry look positive matey.

Turnbull doesn’t need Costello to make life more difficult for him. He’s managing that perfectly adequately. Dennis Shanahan, demonstrating he’s a quality political journalist when he abandons the cheerleader act, today revealed the potentially damaging internal machinations caused by Turnbull’s desire to run the party his way.

Turnbull has two separate problems. One is that his relations with the Victorian branch of the party are under threat, both from his increasingly blatant agitation against Costello’s lingering presence and from his efforts to displace federal president Alan Stockdale and Federal Director Brian Loughnane. Both are Victorians. Loughnane’s obituary has been written before, most particularly after the 2007 election, but he has remained in the job. Turnbull still has Victorian allies — Michael Kroger, Michael Ronaldson, Andrew Robb (unlikely to be very happy about passed over yet again for the shadow Treasurer’s job) — but his leadership is taking on a decidedly Sydney-centric flavour with Hockey and Helen Coonan in top jobs. Having ex-Ronaldson staffer Tony Barry in his office won’t help, given Barry’s level of unpopularity with many Victorian Liberals.

Which leads to Turnbull’s other problem — his management style, which is more suited to the boardroom than politics, where it is all about relationships and egos. There has been substantial turnover of staff in Turnbull’s office even in the time since he has been leader, and the current line-up, led by ex-journo and Downer COS Chris Kenny, doesn’t look too flash. The mystery is why, given money is no object for Turnbull, he can’t recruit a top team of experienced advisers who would need plenty of money to make the switch from the private sector.

Well it’s no mystery at all, because the disincentive — apart from Kevin Rudd’s massive lead in the polls — is Turnbull’s style. Any single adviser is unlikely to be as intelligent and well-informed as Turnbull himself, and he’s not reticent in expressing himself. Advising Turnbull is like advising God. You’re likely to get the impression your views are a tad on the superfluous side.

Between that and Costello and a party room full of MPs happy to shoot first and worry about the public reaction later, Turnbull’s leadership could implode very quickly if there are any further polling reverses. The Liberal Party doesn’t do things by halves. When it goes to pieces, it does so at a rate of knots. It is to be desperately hoped that it doesn’t. Australia doesn’t need to go through an economic crisis with a smug and unchallenged Labor Government. Turnbull is the best hope of the Liberals, however much he sees himself as a CEO rather than a politician.