Now this, by the way, is all based on the presumption that New Zealand First is ropey loose and a pain in the bum. I am happy to be proven wrong. But history is very instructive on this - hopefully we've all learned lessons.
However, this is based around the idea that it's not.
Right, back to Jacinda: it's a three-way - with three major groups and very, very big philosophical differences between parties.
Now Wayne Mapp, the former National MP argues (and I have sympathy for it) that the reason Labour got three terms last time was because National made the error of doing a deal with Winston Peters that turned into the mess it did.
Instead of being in government staggering from crisis to crisis, Labour prepared itself and was set to go when the time came. Why doesn't the same scenario apply today?
As for Bill English - I fully get why the Nats are backing themselves. They're popular, the economy is sound - it's a two-way not a three-way; they're closer to Peters in terms of knowledge and policy.
They've now done deals for nine years - they'd argue they learned from last time.
But I'd have a meeting, have my bottom lines in terms of what I can give up, I'd listen to Peters - and you'd immediately get a sense of whether it's possible or whether it's a mess and delusional.
And as badly as I want to be in power (and this is probably where my argument is delusional because I wouldn't be a pollie chasing power at all costs ... and most of them probably are) for me, walking away isn't the end of the world.
But walk away I would ... if it looked nuts.
I'd call a press conference, I'd tell the world what Winston asked for, tell them why I wasn't going to agree to it - and tell them the destruction of my party and government simply aren't worth it... and I'll see when it all implodes.
And I bet you anything you want ... the party's popularity would go through the roof.
You see it's all about the balance of power - by grovelling to a bloke with nine seats, by looking like you're desperate, but not genuinely having the belief you don't need this.
You start out on the back foot. And that rarely ends well.