Opinion - There is no greater force multiplier in sports than a passionate home crowd.
For the whole Rugby World Cup, all we've heard about is England's long winning record, which is now up to 30 tests. But there's never any mention of the circumstances in which they achieved them, namely that the biggest crowds they've played in front of have almost entirely been for home fixtures.
Aside from playing France, England have had it entirely their own way when having to deal with noise and atmosphere. The closest scorelines they've had in their remarkable run have been a pair of 17-15 wins over the French, one in Exeter and the other in Pau, the latter a stadium that seats just under 15,000.
There will be three times that many at Eden Park on Saturday night and almost all of them will be wanting England to lose.
This is a unique moment for the team that was so heavily favoured going into this tournament, perhaps one that wasn't given enough thought by those making such predictions. England, as good as they are, have never had to play in front of such a large, hostile crowd.
On the other side of the coin, the Black Ferns have had a taste of what it's like to have such a potent Eden Park force behind them twice already.
The opening game and semifinal were in front of loud home support, which skipper Ruahei Demant gave credit to after the one-point win over France, saying that "you guys don't know how much the crowd helps us".
It's not just about roaring on the likes of Ruby Tui, Portia Woodman and the rest of the team.
This will easily be the biggest occasion that referee Hollie Davidson has been a part of, the highest amount of noise she'll have ever dealt with therefore the largest reactions she'll get to any calls either way. Some of the refereeing in the World Cup so far can be charitably described as questionable, so it's not too hard to think that the pressure of such a big crowd will have an effect.
Every time the All Blacks play at Eden Park the 'fortress' line gets rolled out, to remind everyone that they haven't lost there since 1994 and it took possibly the greatest try ever scored to beat them.
The Black Ferns can actually go one better - they've never lost at the country's biggest stadium, with a 10-test win record going back two decades.
However, the lessons of their semifinal will need to be heeded no matter how loud the crowd is. As exciting as the 25-24 win over France was, it did exhibit two glaring areas that are the difference between teams that win World Cups and ones that don't: how you start and how you finish.
Once again it took the Black Ferns far too long to get their hands on the ball and assert their will on the game (an issue that has played a massive role in the All Blacks' woes this season). While they impressively came back to take a one-point lead, their game management at the end was atrocious.
Kendra Cocksedge should know better than to take quick taps in that situation, Santo Taumata almost cost her team the game with a high shot that really should have been a red card and the Black Ferns had to watch Caroline Drouin's penalty attempt fall out of the sky like a duck on the first weekend of May before they could celebrate.
The only positives out of the back end of that game are that France couldn't cash in and that it didn't happen in the final against a better team. Rugby teams' go-to language when reflecting on a performance is how much they learned. It's fair to say that final five minutes was about an entire semester's worth of what not to do.
England will not be as flakey as France. But they can be cut, bled dry and left to die on an Eden Park surface surrounded by fans willing on the home team.
The Black Ferns need to harness the energy of the crowd, get stuck in and then keep their heads, then be carried home to a sixth World Cup title.