Labour's Auckland issues spokesman, Phil Twyford, was yesterday reduced to carping about the cost of the city's transport projects and complaining that the timing for some of the construction was still vague.
"The Prime Minister is talking about a $10 billion commitment to three projects but in his speech he was completely silent about how he is going to pay for them.
"Where on earth is the money coming from?"
Key could have said "You work it out chump, I'm unlikely to be PM by the time a future New Zealand Government has to seriously put its hands in its pockets".
But he later confined himself to telling journalists it could come from various sources, including (take that, Labour!) the Future Investment Fund, into which his Government is tucking the proceeds of its partial privatisation programme; the Land Transport Fund, which holds the proceeds of petrol excise tax and road-user charges; taxpayers through the Consolidated Fund and even the private sector through some nifty public/private sector partnerships (PPPs).
What Key didn't say - and won't until the Government has surety on the numbers - is that the fiscal track is on an upswing and there is a strong possibility Finance Minister Bill English will be able to post a Budget surplus well before 2014/2015 (some Beehive insiders suggest the surplus milestone could be reached even by the end of this year, though that looks optimistic).
When I put the question to him down at the media scrum at SkyCity's conference centre, Key deftly sidestepped it.
But he later conceded that getting government debt down to under 20 per cent of GDP would be the next priority.
In other words, yes, the fiscal track is moving very nicely, thank you.
It must be excruciatingly dreadful for Labour.
Its "show me the money" challenge (delivered without the panache that Key used to slaughter former Labour leader Phil Goff during a debate at the last election) fell flat. Its party strategists know that pushing that line of questioning simply risks Labour being seen as churlish.
But what really galls the Opposition is the fact that Key has stolen Labour's thunder, particularly in Auckland.
Key is now "besties" not only with Auckland Mayor Len Brown, who was positively radiant as he openly rejoiced yesterday that the Government was "backing Auckland", but also with Christchurch Mayor Bob Parker.
Brown will pocket Key's commitment as an endorsement of his own mayoralty, given that he based his first run at the top job on delivering three big-ticket, next-generation transport projects.
And Christchurch mayoral challenger and Labour MP Lianne Dalziel was reduced to complaining from the sidelines as Key and Canterbury Earthquake Recovery Minister Gerry Brownlee cosied up publicly with Parker to announce agreement had been reached on $4.8 billion of investment in Christchurch - $2.9 billion of it coming from the Crown and $1.9 billion committed by the Christchurch City Council - so that projects like the new stadium and a convention centre can proceed.
Key couldn't resist having a flick at Labour during yesterday's stand-up, telling reporters he could understand why the public wasn't warming to Labour because it was "too negative".
What John Key has announced in Christchurch and Auckland in successive days this week is incredibly clever politics. Those on the Left who deride Key as a political lightweight have been left with an entire omelette on their faces.
Key may not have spent his entire adult life frequenting the same smoke-filled back rooms and union halls that they have, weighing up everything from a political perspective. But that does not mean that the Prime Minister is any less skilled at the Dark Arts of politics as they pride themselves on being.
Labour has been out-boxed this week. The public now knows exactly which of the big-ticket items in Christchurch will proceed, and who is paying for what. And a blueprint has been laid out for huge investment both in roading and in public transport in Auckland over the next 15-20 years. John Key has even been canny enough to leave room for the CBD rail loop to come on-stream sooner should growth in the Auckland CBD happen faster than anticipated.
And as O'Sullivan notes, "the fiscal track is moving very nicely, thank you"; excellent news indeed. What a coup it would be for the PM if the fiscal track had moved along so nicely that Bill English was able to announce a small budget surplus for 2013-14, instead of 2014-15, as forecast. We certainly wouldn't bet against it.
This has been National's week on centre stage; of that there is no doubt whatsoever. We wonder if those 65 days until the beginning of spring can't come around soon enough for David Shearer.