Tony Abbott is digging in behind his chief of staff, Peta Credlin, in an extraordinary public way. But one of his main arguments for backing her is exactly the same reason some of his colleagues think she should stand aside.

I am not referring to the reason the prime minister gave in an interview on Friday – that those within the Coalition backgrounding against his trusted confidante and long-term adviser are motivated by sexism.

Listening to the complaints and the stories – they started in opposition and have grown to a crescendo in recent months – I have always factored in the strong possibility they include an element of pushback against a woman exercising a chief of staff’s considerable powers.

But even if that is the case, and even crediting the prime minister for appreciating his staffer’s undeniable talents, dedication and loyalty, the deep resentment within the party is real and so is the public disunity that resentment is causing.

By chastising his colleagues and suggesting gender may be motivating their attacks Abbott has only turbocharged that resentment and the public discussion of the government’s disunity.

And of course suggesting sexism is behind the criticism also draws the obvious cries of hypocrisy, given that he responded to Julia Gillard’s famous misogyny speech by demanding that Labor stop “playing the gender card”.

‘’Just because the prime minister has sometimes been the victim of unfair criticism doesn’t mean she can dismiss any criticism as sexism or she can dismiss any criticism on gender grounds,’’ Abbott said at the time.

But the real clue to the prime minister’s defence is the other thing he has said in defence of Credlin in recent weeks, that she is “the fiercest political warrior I have ever worked with”.

He means it in a good way. But others at the most senior levels of government insist the Credlin problem stems precisely from the fact that she sees herself as the warrior defending the prime minister at every turn.

The list of complaints is long and familiar.

That she tightly controls access and information, meaning the prime minister does not hear contrary sources of advice. In fact he hears very little advice without Credlin present, which makes it particularly difficult for senior figures to give the prime minister advice about her and her role.

That she has issues with anyone in the prime minister’s office, or any other office, who challenges or disagrees with her.

That she “oversteps the mark” – countermanding ministers and participating in top-level meetings and even cabinet discussions in ways senior Coalition figures believe is inappropriate for an unelected official. (Sources say in recent months she has stopped intervening in cabinet discussions.)

That ministers hear about policy decisions affecting their own portfolios when they are leaked to the media. Backbenchers hear about most government decisions that way. The treasurer didn’t know his own departmental secretary had been sacked. Senior Department of Foreign Affairs officials complain they have to try to piece together what has happened at important prime ministerial meetings with foreign leaders, because Dfat officials have been excluded and no one has taken notes.

Business representatives have complained that Credlin has answered questions they addressed to the prime minister. She vetoed the desired candidates of multiple ministers for senior positions on their staff, and even dictated who could be employed in electorate officers. Ministers complain of micromanagement in the prime minister’s office, with backlogs of documents and briefings requiring approval or decision.

The prime minister’s office vetoed the foreign minister’s initial request to travel to the United Nations climate meeting in Lima – something the minister herself put on the public record. And the prime minister’s office raised serious last-minute doubts that nearly derailed the environment minister’s deal with Clive Palmer which allowed the government to legislate its Direct Action plan.

Credlin has been by the prime minister’s side from almost the moment he took over the leadership of a Coalition split asunder and demoralised after its internal ructions over support for the Rudd government’s carbon price. Her gladiatorial, win-every-day, with-us-or-against-us style was aimed at one thing: dragging the Coalition’s primary vote up from where it was languishing at the time, 35%. Inch by inch those improving numbers gave her boss greater job security and credibility, loosened the pockets of donors and enlivened the backbench with hope. They took Tony Abbott to within a whisker of winning in 2010 and in 2013 delivered him the Lodge. The prime minister has very good reason to highly value the role she has played.

But her critics say her style is not as well suited to government and contrast Abbott’s office with John Howard’s office, where the chief of staff and political enforcer roles were split between Arthur Sinodinos and Tony Nutt, where contested advice was actively encouraged and where the proper roles of staff and elected officials were strictly adhered to.

These are, of course, all stories from her detractors. And they are anonymous, while several of the government’s most senior ministers have recently been prepared to go on the record with strident comments in her defence. And there may indeed be an element of “piling on” criticism of Credlin to deflect attention from everyone else’s contributions to the government’s political woes.

But – fair or unfair – the criticisms are now rife, and the prime minister himself has now acknowledged that they are coming from colleagues, and has sided with his long-term staffer.

His colleagues were utterly dismayed by Abbott’s “sexism” defence on Friday, because it demonstrated that he has not listened to any the detailed reasons for complaint. They say that by digging in beside her, Abbott is digging himself into a hole. They don’t need to point out that the Coalition’s primary vote is back down to 37%.