For the first time in quite some time, the National minority Government this week looked a bit ragged around the edges. Not hugely so, mind you. But wariness seems to have succumbed to a degree of weariness.
Or so seemed the case with the prime minister, who was uncharacteristically out of sorts during Parliament's question time on Tuesday and Wednesday afternoon.
Mr Key looked distinctly uncomfortable when quizzed about ministerial responsibility (his) for the purchase of the replacement fleet of luxury BMWs for ferrying Cabinet ministers to and from appointments.
Mr Key resorted to that old stand-by that the purchase had been an "operational matter" for the chief executive of the Department of Internal Affairs - not him - and the decision was therefore not his responsibility.
This defence may technically be correct. But it has been devalued so much over the years, it now sounds like an excuse for inaction.
The public does not buy the line that ministers cannot intervene to stop something happening in their portfolios. The public certainly won't buy it from someone who is normally both savvy enough and swift enough to rectify things before they start turning to custard.
Furthermore, emails released under the Official Information Act show officials were rather keen to get the nod or otherwise from Mr Key before going ahead with the purchase, given his role as the minister responsible for Ministerial Services, one of the branches of Internal Affairs.
For one reason or another, that message went to the Prime Minister's Office but never got to Mr Key. Had it done so, the longstanding contract with BMW may still have been too watertight for Mr Key to keep the new models off Parliament's forecourt. But then he could have at least said he had tried.
Alongside the Government's $43 million loan to media company MediaWorks and the bickering over South Canterbury Finance, the BMW purchase is one of the stories which just refuses to die.
They are recurring nuisances nagging away at the Government, the latest being the Auditor-general's decision to investigate whether Sammy Wong, the husband of former MP and Cabinet minister Pansy Wong, misused parliamentary travel perks to conduct private business.
Such sideshows barely rated when the media's focus was concentrated elsewhere than on the Beehive, first on the Christchurch earthquake and then on the turmoil within the Labour Party.
But politics is returning to normality.
Although this week witnessed the near-unanimous fast-tracking through Parliament of the law setting up the new, all-powerful Christchurch Earthquake Recovery Authority, Labour clearly no longer feels obliged to maintain the truce not to exploit the February 22 disaster for political gain.
Things were also returning to normal on another front. National might have hoped the fallout from Labour's internal dust-up over the "gaggle of gays" musings of Damien O'Connor would have lingered in the political ether. It didn't. Mr O'Connor's self-interested moaning about the procedure for compiling the party's list was the final straw for Labour MPs conscious the party was drifting dangerously close to last orders at the Last Chance Saloon as far as voters are concerned.
Showing some early mettle, Labour's new president Moira Coatsworth wasted few words in rubbishing what will (if it ever happens) be a Quixotic crusade on Mr O'Connor's part to change the rules.
Exasperated colleagues then chewed the MP up behind the doors of the party's weekly caucus meeting before spitting him outside for the waiting media to devour what was left of him.
Making an example of Mr O'Connor seemed to provide some catharsis for the caucus, which got a further fillip in successfully turning the tables on Mr Key in the House.
Labour's new strategy involves directing more questions at the prime minister in the belief that the more ground he has to cover in preparation, the more likelihood of inconsistencies in his answers.
The obvious question is whether Labour's tactics in Parliament will make one iota of difference come November's election.
While not necessarily vote-changers on their own, a common thread connects the BMWs, the loan to MediaWorks, the taxpayer-funded bail-out of investors in South Canterbury Finance, the Sammy Wong case and even the $2 million plastic "tuppawaka", which Labour's Shane Jones has caned so vigorously.
Labour cites them all as examples of how, despite the cries from Mr Key and Bill English that times are tough, the politics of privilege are thriving under National.
Labour claims National is hellbent only on helping its well-off mates.
Witness last year's tax cuts, which disproportionately favoured higher income earners while leaving those on lower incomes facing a hike in GST and other increases in the cost of living.
In contrast, Cabinet ministers get their fancy cars, speculative investors in South Canterbury Finance keep their money plus interest and struggling MediaWorks gets a loan to tide it over while it restructures its balance sheet.
All this looks very much like the genesis of an election campaign strategy. Much will hinge on the extent to which next month's Budget complements the favouritism that Labour claims is fast becoming a hallmark of National policy.
Much hinges on Phil Goff also picking fights he can win. This week he hammered Bill English for admitting the obvious - that the 30% wage gap with Australia offers a competitive advantage in attracting jobs and capital to this side of the Tasman.
Mr Goff then seized on the latest Statistics New Zealand figures covering long-term and permanent departures to Australia.
These show nearly 4000 New Zealanders crossed the ditch in February - a figure which Mr Goff argued showed exactly what people thought of Mr English's "bizarre" statement on the wage gap.
Check the figures more closely, however, and you discover more than 4300 New Zealanders left for Australia back in February 2008, when Labour was still in power.
Mr Goff could have come an awful cropper when he questioned Mr Key about the figures in Parliament. But Mr Key had not come armed with the necessary ammunition. He disputed Mr Goff's figures but left it at that, thereby letting Mr Goff off the hook. The prime minister is unlikely to be so generous next time.
- John Armstrong is the The New Zealand Herald's political correspondent.