Before those on the left misinterpret that statement as trying to absolve Key in advance, they might like to ponder the electoral repercussions if Dotcom's assertions turn out to be little more than hot air.
Key will stand or fall on the strength of Dotcom's case. The time has come for the country to hear it and appraise it. The time has come for Dotcom to cut the babble and prove Key is the one talking nonsense when he insists that until the eve of the police raid on Dotcom's Coatesville mansion he did not know of Dotcom, let alone that Dotcom was living in his Helensville electorate, or that Dotcom was the subject of a FBI investigation even though the intelligence agencies for which Key has ministerial responsibility had known for at least 15 months before the raid that was the case.
If the Prime Minister has not been telling the truth, then, as Dotcom and his supporters argue, it is a matter of paramount importance even if what they are arguing about could hardly be more trivial.
It follows that New Zealanders are surely entitled to know whether or not Key's word is devoid of trustworthiness. And they should be told today. Not tomorrow. Not next week. And most surely not when it is most politically advantageous for the Internet Mana leadership - Dotcom, Laila Harre and Hone Harawira.
To keep everyone on tenterhooks until Dotcom reveals all at an Internet-Mana Party rally at the Auckland Town Hall five days before September's election may be a cunning tactical move, but it is also a cynical one.
It is also not risk-free. It could yet backfire on Dotcom and his party.
It is clever because 20 per cent or more of those who vote do not make up their minds until the final week of the election campaign. That percentage is probably even higher among the non-aligned voters Internet-Mana is targeting.
If Dotcom delivers the goods, it will be a huge story which would throw Key deep into the resignation quicksand.
As was the case in 2011 with the Epsom cup of tea - the tete-a-tete between Key and Act's John Banks - the side-effect could be that Opposition parties other than Internet-Mana, having planned their campaigns and, more specifically, their advertising budgets, to reach a crescendo in the final week before polling day, could instead find themselves peripheral to the action.
Dotcom's gambit is even more high-risk for Internet Mana. Tackling any prime minister, let alone one as popular, smart, adept and seemingly Teflon-coated as Key, is not a task for the faint-hearted - or the over-confident.
The stakes do not get any higher than this. Foolishly, Dotcom has raised expectations to a level which is so high that falling short even by a small margin will result in him being torn apart by the media and becoming subject to ridicule.
A comparison with which Dotcom might well acquaint himself is the argy-bargy over Don Brash's embarrassing supposed quip as National's leader to a visiting delegation of American senators that Labour's anti-nuclear law would be "gone by lunchtime" if National won that year's election. National went into damage-control and denied Brash had said it. Brash could not remember. But clearly he had. Even so Labour never quite pinned the remark on Brash to the degree it had hoped for.
If Dotcom's case similarly relies on hearsay or circumstantial evidence in any way, he would be best to work on an exit strategy - one in which he exits now. Or at least as quickly as he can without losing too much face.
Key, in contrast, has said little that he might later regret, but done much to try to second-guess exactly what Dotcom seems to think he has on him.
When Dotcom first suggested Key had known of him some time before Key claims to have heard of him, the Prime Minister and his staff in Wellington and Helensville searched desks, filing cabinets and computer records for anything that might be incriminating even in the slightest. They found nothing.
Lastly, Dotcom should ponder over this scenario. If Key is caught out, he will probably apologise and then make his credibility the issue for the final days of the campaign.
He will be able to wager his huge stocks of popularity on voters viewing any conflict over what he said about Dotcom and what he knew about Dotcom as a minor indiscretion.
Again, the argument is probably too trivial to destroy Key. But Dotcom needs a change of government if he is to have any hope of avoiding extradition to the United States. And Key's hard-to-believe ignorance of his existence is one of the few means Dotcom has of securing such a change.
