Other ministers present greater challenges to Ardern, particularly those in the Maori caucus.

Clare Curran's departure will be a relief for Prime Minister Jacinda Ardern who has been plagued with political management issues since returning from maternity leave.

But of all the management issues confronting Ardern, Curran's is the easy one.

She cut herself loose rather than endure weeks of further scrutiny and pressure and guilt about the damage she was doing to the Government.

Other ministers present greater challenges to Ardern, particularly those in the Maori caucus who come with a built-in support base and where a challenge to one's mana can be a challenge too all.

Meka Whaitiri remains a minister on suspension pending an inquiry into an altercation with a staff member.

As was evidenced on Thursday when Whaitiri returned to Parliament for the third reading of the Rohe o te Wairoa treaty settlement bill, she has firm support within the Maori caucus and from her electorate.

Willie Jackson, co-chair of the Maori caucus with Whaitiri, behaved like Centurion guard around her on Thursday, and has already issued statements of solidarity.

He is not the first person to suggest that the trouble in which Whaitiri finds herself is a media-made problem, rather than anything she may have done.

The employment inquiry by Ministerial Services will look purely at the case, not at Whaitiri's previous reputation.

And if it comes back with a disputed finding, a she-said she-said, Ardern will have no firm basis for firing her.

Fortuitously for Whaitiri, Curran's departure tips the balance in favour of her keeping her ministerial job, and being on notice with a final warning.

National would be in no position to cry foul or to target Whaitiri given that under its own watch, some ministerial staff are thought to have departed with non-disclosure contracts and presumably big payouts.

National's best targets will continue to be weak ministers.

And Curran was not the only minister floundering during Question Time on Wednesday.

Kelvin Davis, Labour's deputy leader was Acting Prime Minister because Ardern and Winston Peters were both in Nauru for the Pacific Islands Forum.

It was during his answers in his own portfolio as Minister for Crown-Maori Relations that he drew a barrage from the Opposition benches.

Davis isn't a bad Minister of Corrections. He had preparation for that in Opposition. It is largely an operational portfolio and he knows his stuff.

But he flails when asked questions about his Crown-Maori Relations portfolio.

That is hardly surprising given he is the first Minister of Crown-Maori Relations and his first job was to go around the country and find out from Maori what they wanted his job to be.

And the answer had yet to be confirmed by the cabinet.

That is a gift for a clever Opposition politician like former Treaty Negotiations Minister Chris Finlayson - and Davis looks like an accident waiting to happen.

On Wednesday, Davis was facing questions from Finlayson over what he exactly does in Crown-Maori Relations.

The Opposition erupted when Davis said: "An announcement will be made very shortly about the scope of the portfolio."

It was tantamount to saying "I don't know what I'm doing, but we'll find out soon."

Speaker Trevor Mallard failed to see what the uproar was about and said cryptically there were "some interesting aspects to that reaction," which some National MPs took to mean that Davis was being targeted a as a Maori minister.

(Incidentally, Mallard did not suggest that Clare Curran was being targeted as a woman minister).

It was reminiscent of Mallard supporting objections by the Government when National drew attention to close family marae links between Wally Haumaha and New Zealand First, which had not been declared to the cabinet before approving his appointment as Deputy Police Commissioner.

If it was something of a caution to National to be careful in its criticism of Maori, it is an unwelcome development in New Zealand politics.

Davis was a successful school principal, a strong local MP and was always going to be cabinet material. But he was elevated into the deputy leadership of the party suddenly.

In a merit-based contest, Grant Robertson, Ardern's political soul mate, would have been her deputy but the Maori caucus used its leverage and Davis got the job in a swift and clean transfer.

It was an appointment acclaimed for its symbolism, and with so much celebration within Maoridom that the reason he got it has never been questioned.

National throughout its three terms in Government had worked closely with the Maori Party and elevating Davis was a way to show that Maori would not only get a seat at the table in Labour but would be part of the top table calling the shots from within the big party.

It gives Davis the seniority to hold the new Crown-Maori Relations portfolio, but not necessarily the political acumen or experience to handle it well.

With so many large issues unresolved, the potential for political mis-steps is high.

While the scope of the portfolio is yet to be confirmed, Davis will be responsible for developing a way to deal contemporary claims.

He is the minister responsible for working out who the Crown deals with in Maoridom, what values will underpin that engagement.

The values are yet to be defined. An announcement will be made soon.