Social cohesion is such a key to the alert levels that Prime Minister Jacinda Ardern hinted yesterday it was a major factor in moving Auckland out of level 4 two weeks ago.
Experts called it a calculated risk at the time, and Professor Michael Baker said he would be very surprised if the extra freedoms of level 3 didn't eventuate into higher numbers within two weeks.
That now appears to be happening, meaning if Auckland had been on a knife edge before, today that edge is only sharper.
Yesterday the number of unlinked cases in the past fortnight jumped to 23 (24 if we include both Waikato cases, only one of which was included in yesterday's numbers, and 25 if we include the case in Auckland Hospital last night).
The previous days it was 10, 9, 15, 15, 7, 7 and 5.
There were three active subclusters on Wednesday. Now there are five.
The R value - the number of people the average case infects - in Auckland at level 3 is now higher than 1, according to Covid-19 modeller Professor Michael Plank, with the caveat that it's hard to gauge while case numbers are so low.
That means the outbreak, while still relatively controlled, is growing.
And with the day's numbers reflecting what happened in the community one to two weeks ago, don't be surprised if case numbers continue to trend up.
Part of the reason is because a majority of sick people don't get tested, and in this outbreak, the virus has crept into circles - including gangs and the homeless - who are even less responsive to testing or contact tracing methods.
There's a recognition of this from testing teams, who have tried to reach every corner by going door to door in specific suburbs, and by testing all 40 of the emergency and transitional housing sites that have been deemed medium to high risk.
If all of this surveillance testing was finding no cases, and testing rates in those suburbs of concern across south and west Auckland remained high, we could be more confident of a flicker of level 1 light at the end of the tunnel.
But a small number of cases continue to pop up, for example in Clover Park, even when the door-knocking was not received with open arms; the last data from the ministry had only nine out of 100 households agreeing to be tested.
People have also continued to turn up in Waitakere, Middlemore and Auckland City Hospitals for reasons unrelated to Covid, but who then later tested positive.
And now we have a case who left Auckland and drove to Palmerston North, and cases in the Waikato whose infections have today been linked back to Auckland.
The chances of a wider outbreak in the Waikato are hard to gauge without knowing more about the cases' movements, but there are good signs: they haven't left the region, and their ages (40s and 50s) suggest a quieter social calendar.
All of these cases paint a picture of ongoing, undetected community transmission in Auckland.
"I think it's looking extremely difficult - I'm not going to say impossible - to eliminate this outbreak," says Plank.
"It's not hugely widespread. But we're one step behind the virus rather than one step ahead of it."
This means moving Auckland to level 2 this week - and for who knows how many more weeks, given the stubbornness of the Delta tail - would be like throwing kindling on the embers on a windy day.
Remember level 2, even with the Auckland boundary remaining, means no household bubbles, gatherings up to probably 50 people at first, regional travel within the Auckland region, and some 256,000 people who are still unvaccinated out and about.
Conditions would be ripe for the remaining embers to flare up into uncontrolled transmission, which has happened in so many other countries, inflicting pain, suffering and death.
Ardern bluntly said yesterday she had no regrets about moving Auckland out of level 4, and has all but ruled out moving the city back into level 4.
Staying at level 3 will at least buy public health teams more time to continue their heroic hunt for those remaining cases by engaging with those marginalised communities.
Strengthening measures at the Auckland boundary would also help, but while Ardern is considering mandatory vaccination for those workers, she has already questioned whether testing them more than once a week is practical.
Rapid antigen testing, while used extensively overseas, is only being piloted at Middlemore Hospital, and it also carries the risk of a false negative result making a possible carrier less vigilant.
But it could complement the surveillance testing if it was rolled out across the Auckland boundary, as well as in the west and south Auckland suburbs where cases continue to appear.
And then there's saliva testing. Rako Science can process 10,000 of these a day. How much are we doing, and can we do more?
Announcing vaccination requirements for certain high-risk activities could also help nudge up first dose vaccination rates.
Meanwhile, the social cohesion holding level 3 in Auckland appears to remain intact; Waka Kotahi's transport data shows movement consistent with level 3 movement last year.
Ardern will today lay out a roadmap to level 2 in Auckland, in part to appease any anti-lockdown tremors. That will likely look into what aspects of alert level restrictions are lower risk and might be able to be eased.
But it's hard to see health officials recommending the end of household bubbles while there are still signs of undetected transmission, and with vaccination levels still relatively low.
Level 2 would only be viable if contact tracers can stay ahead of the virus, but Delta is so transmissible that they've been unable to completely ring-fence this outbreak, even with the help of lockdown restrictions.
Creating a Fortress South and West Auckland and freeing the other areas of the city also seems fraught, given how hard it would be to keep people who live in one street from going to a neighbouring street beyond the fortress.
The Waikato boundaries that came into force overnight are already a high-trust model because there are too many ways in and out to be policed.
Vaccination is the game-changer, and Ardern has already said that 90 per cent coverage of the eligible population changes the lockdown equation.
Almost 84 per cent of Aucklanders have had one dose, but with six weeks in between doses, hitting 90 per cent is still some way off - if it happens at all.
Another way to move Auckland to level 2 is if social cohesion unravels and the Government's hand is forced.
But with hundreds of thousands of people still not fully vaccinated, doing so would resign the city to the same fate as Sydney and Melbourne.
And that would be a tragedy which, at this stage, can still be avoided.