According to the considerably well-connected conservative commentator Niki Savva, the Prime Minister has made wholesale changes to the advisory staff in his office.

This is a good thing, given prime ministers are usually only as good as the people who advise them.

Recent Australian political history bears out this maxim. The turbulent early days of John Howard’s decade-long administration were only brought to an end when the strategic-minded former Treasury boffin and Howard’s head of policy, Arthur Sinodinos, replaced the tactician Grahame Morris as the PM’s chief of staff.

Other PMs were less fortunate. The administrative nightmare that distinguished Kevin Rudd’s time in office was due at least in part to his inclination to surround himself with wunderkinder who had no experience in matters of state.

Julia Gillard had no such “excuse” for the poor political decisions that weakened her position and left her exposed to Rudd’s machinations. She wasn’t helped by her communications director, John McTernan, whose skill set was more suited to the British political environment, where it was honed, than the antipodean version.

More recently, Tony Abbott’s brief tenure as PM will indelibly be associated with his chief of staff, Peta Credlin, upon whom he depended almost exclusively for political counsel. Credlin may well have got the Coalition into government, as she claims. And the fierce discipline she imposed on Coalition MPs is sadly lacking now. But Credlin, the political warrior in opposition, was not suited to government. Her unforgiving management style, selective nepotism and almost exclusive focus on blue ties, flag-infested podiums and national security hype ultimately let Abbott down by widening the disconnect between the PM’s approach and the more moderate one preferred by the majority of voters.

[Why the media are so fascinated by Peta Credlin]

It would be fair to assume that having vanquished and succeeded Abbott, Malcolm Turnbull would have been awake to the critical need to surround himself with the very best advisers possible.

Turnbull started out reasonably well, appointing an experienced administrator as his chief of staff, the well-respected former department head Drew Clarke. This was Turnbull’s version of Howard putting Sinodinos in the role. In further emulation of the Howard model, Turnbull also kept the political adviser responsibilities separate from that of the chief of staff, appointing long-time adviser Sally Cray as his principal private secretary.

Legendary political hardman and now federal director of the Liberal Party Tony Nutt performed this role in Howard’s office.

Turnbull’s staff also includes legendary advancer, Vince Woolcock, who happens to be married to the aforementioned Niki Savva.

According to Savva’s column this week, the PM is “beefing up” his office, taking on former Abbott press secretary Mark Simkin as well as appointing Simon Atkinson, who was chief of staff to Mathias Cormann, to do strategic work on policy. Turnbull’s former press secretary David Bold will become the contact point for the crossbenchers.

That all makes good sense. But Turnbull also appointed a new economics adviser: Peter Hendy, the failed Liberal member for Eden-Monaro who was a leader in the orchestration of Turnbull’s move on Abbott.

Hendy’s appointment points to a seeming blind spot in the Prime Minister’s perception of who is best equipped to provide him with sound advice. A blind spot, it must be said, that mimics Abbott’s blinkered view of Credlin’s capabilities.

As an economist, Hendy is capable enough, even though the bone-dry economic principles that shape his analysis and advice are somewhat dated in today’s post-Piketty world. Accordingly, Hendy will be in no position to assist Turnbull in responding to the compelling arguments on social capital that will be advanced by Labor’s economic champions such as the volunteer shadow minister Andrew Leigh.

But we all know why Hendy got the job; it was an act of charity by the PM for one of his key lieutenants. Labor does it too, with perhaps the most notable example being John Brumby, who was a federal MP for seven years, then chief of staff to a federal minister before being elected to the Victorian Parliament and eventually becoming premier.

However, Hendy is no Brumby. And by giving him such a consolation prize the PM has added yet another item to the list of bad decisions that he’s made this year.

The list is depressingly long despite Turnbull having been PM for less than a year. It includes floating and then backing away from increasing the GST; suggesting the states could raise their own income tax; basing the government’s economic agenda almost entirely on a tax cut for business; insisting on running a positive election campaign; appointing Christopher Pyne as the minister for pork-barrelling; and rushing the arrangements for the royal commission into youth detention in the NT.

And just when we hoped it couldn’t possibly get worse, the PM denied our pleas by responding to Labor’s populist but popular demands for a royal commission into the banks by requiring the banks to subject themselves to the annual scrutiny of a parliamentary committee.

Yes, a gaggle of self-inflated backbenchers will get to speak sternly to bank CEOs each year. This level of scrutiny won’t necessarily be the same as being whipped with a wet lettuce leaf, but it won’t be any worse. And it is unlikely to meet voters’ demands for action against the banks.

These are the decisions that Malcolm Turnbull has made in consultation with the advisers — staff as well as colleagues — with whom he has chosen to surround himself.

With the exception of Hendy, who is yet to start in the PM’s office, it’s hard to fault the staff that have been assembled by the PM. So it does not appear that the bad advice is coming from the PMO. More likely is that Turnbull is being poorly served by the inner sanctum of colleagues who congregate around him.

These MPs include James McGrath, a former political strategist and deputy director of the Liberal Party, who should have finely tuned political antennae. Another is Scott Ryan, a former political scientist, lobbyist and staffer.

But the PM’s closest adviser is reported to be the man who furnished PM John Howard with obviously wise counsel during his tenure — Senator Arthur Sinodinos. The Senator is widely respected throughout political circles for the political acumen he demonstrated during the Howard years.

But if the evidence given by Sinodinos to the NSW ICAC is any indication, those smarts seem to have eluded the former chief of staff since he left Howard’s office and later took on a board position at Australian Water Holdings.

Perhaps the unfortunately political reality is that Sinodinos has lost his touch. The litany of poor decisions made by Turnbull — presumably in consultation with Sinodinos — is a growing indictment on the political capability of both men and could ultimately result in the premature conclusion of their time in high office.

Turnbull’s shakeup of his personal staff is an acknowledgement that the PM needs to receive better quality advice. But if he does not also assess and improve on his sources of from colleagues, Turnbull may completely overlook the necessary solution to the problem.