A successful conference at the weekend and a decent poll ensured it was a chipper pack of National Party MPs who rolled up for Parliament this week.
Morale is the most precious commodity for any Opposition, and National had needed a wee boost.
His one-point rise to 6 per cent as preferred Prime Minister, and National's two-point advantage over Labour clearly emboldened leader Simon Bridges.
Bridges will not have missed that Ardern's ratings as preferred PM had slipped from 51 per cent in April – soon after the mosque attacks – to 45 per cent in June, to 41 per cent in July.
He clearly deduced the stardust was reaping diminishing returns, and tried to hasten the process.
So up he popped with his claim she was a "part-time Prime Minister", taking great care to specify this was because she had gone off to Tokelau for five days rather than staying to tend to issues such as Ihumātao and protests over Oranga Tamariki.
• 'Part-time PM': Simon Bridges attacks Jacinda Ardern over Tokelau trip
• Grant Robertson suggests Bridges' PM criticism has 'sexist overtone'
• Mike Hosking: Why has Jacinda Ardern gone overseas yet again?
• Kate Hawkesby: Bridges sexist for calling out PM? I don't think so
He argued Ardern could just as well have done that trip during the recent three-week recess rather than a sitting week.
For good measure, Bridges coupled it with a couched dig at Ardern for again appearing in international media, saying he would never get on the cover of Vogue - "but I am going to release good policies".
Grant Robertson suggests Bridges' PM criticism has 'sexist overtone'
Claire Trevett: Building Bridges - inside the latest political poll
Latest poll: National rises against Labour, as Ardern dips in preferred PM stakes
It was the most direct attack Bridges has mounted so far, and was more for the benefit of core National Party voters than anything - those supporters who want to see the leader take Ardern on, and likely put a bee in Bridges' ear about it at the party's conference.
But the other aim was to tap into any underlying sentiment that the Prime Minister was not focused on what was happening at home because her attention was elsewhere.
Bridges was walking something of a tightrope, given any questioning of the PM's commitment is something of a sacred cow and easily interpreted – as indeed it was by many – as questioning her ability to juggle motherhood and her job.
It had the desired effect of being a red rag to a bull.
Finance Minister Grant Robertson stepped up as the Great Defender, berating Bridges for "sexist overtones", "dirty politics" a "desperate attack at a personal level toward the Prime Minister." and being disrespectful to the people of Tokelau and to the position of Prime Minister.
It was a rather overwrought reaction to a comment most people could judge for themselves.
It is also ridiculous to suggest the PM is immune from being criticised by the Opposition over her priorities purely by virtue of being the PM.
In that regard, Robertson's response was also rather rich given Robertson himself could be accused of being disrespectful to the office of the Prime Minister when that office was held by former Prime Minister John Key.
Labour MPs frequently referred to Key's personal wealth and mocked him for reaping photo ops – from playing golf with US President Barack Obama, to visiting the All Blacks' dressing rooms.
The label often used of Key was "Smile and Wave" – a nickname designed to send pretty much the same impression that Bridges' "part-time PM" label was.
That particular phrase appeared to originate from former MP Lianne Dalziel in early 2010, when she said in Parliament Key brought to mind the movie Madagascar.
In that, whenever anything went wrong, Skipper the Penguin would say "just smile and wave, boys, just smile and wave".
Other MPs picked up on it, and it became a regular refrain.
It did not work at all – and it is perhaps notable that it has not been used in Parliament since the 2014 election when Labour was delivered a crushing defeat.
In all likelihood, Bridges will learn the same lesson Labour learned about "smile and wave".
That lesson is that the public make up their own minds about such matters based on what they see of a PM rather than what others tell them.
But Robertson could also learn from National.
Key's response was to simply dismiss such slurs as the meaningless nonsense they are by completely ignoring them, thereby depriving them of oxygen and relevancy.
Rising to them simply gave the impression that the criticism had cut a bit close to the bone.
The reason for all this jostling about was contained in another figure in that 1 News Colmar Brunton poll.
The most important figure was 13 per cent.
That was how many undecided voters there were, watching and waiting before deciding who would get their tick - if anyone.
All parties need them and all parties will be assiduously courting them, through a mix of boasting their own credentials and trying to sour their opponents.
On the matter of the name calling, perhaps the best advice of the week was offered up by Australia's Speaker, Tony Smith, who observed of a squabble in the Australian Parliament:
"Out there in Voterland they are just watching a couple of mouths move. You're on mute."