The last few weeks have shown that if any of the Six Nations teams want to win the next World Cup, they've got to develop a more expressive style.
You can't go out with the aim to 'just do enough' - you've got to go out and win it. The Northern Hemisphere sides all seemed to revert to type in the big games and played conservatively.
And you won't beat the top teams - certainly not the All Blacks - by playing for penalties and relying on your kicker.
What frustrates me is that pretty much all of the teams in Europe are capable of varying their game. I wish they had brought the mindset from the last day of the Six Nations, when there were 27 tries scored in three games.
It's not all doom and gloom for the Northern Hemisphere: Scotland got the wooden spoon in the last Six Nations, and they were a controversial decision away from beating Australia; Wales pushed South Africa close despite missing pretty much an entire backline; and it's hard to judge Ireland when they were without five key players.
Having spent a long time in the Northern Hemisphere, I don't think there's a massive difference in natural talent. It's about confidence to play a high-skilled style of game.
In New Zealand, people want to play a more expressive brand. Back home, everyone - even the tight-five forwards - grows up playing touch rugby. That's a big difference: they develop a greater number of skills from an early age.
They are expected to have those skills.
It's perceived back home that in the Northern Hemisphere, a lot of teams don't play any rugby - and some don't. Leinster are an exception - we've always tried to play expressive rugby, which is one of the main reasons I came here. I didn't want to chase high kicks.
Of course, not every Southern Hemisphere team runs the ball from everywhere. South Africa pretty much kick it out of their half, and put pressure on the opposition.
Argentina didn't do anything flash last week, but it was an expressive brand of rugby, executed at a very high level.
Even the Julian Savea-inspired All Blacks didn't do anything too fancy against France. Okay, there were offloads but what they did was play what was in front of them.
It's about being able to vary your game-plan depending on how the match is unfolding. The key is to have the skills, and trust them in big games.
In Europe now, things are changing slowly. Skills are improving. But people have learned their trade in wet-weather rugby. It takes time. And time isn't something that international coaches get a lot of. The biggest problem for Northern Hemisphere sides trying to develop a style is that coaches are under pressure.
I think the top European teams have the talent to play the way the All Blacks do. There's not a huge gulf in terms of ability. It's about trusting a wider game-plan and playing it regularly. You can't just flick a switch and play a different brand of rugby and expect it to work immediately.
How do you develop a new philosophy when there's so many demands on you to just win the next competition?
Sometimes, you have to suck up a few bad results. Scotland had the most encouraging World Cup of any of the Northern Hemisphere sides but it took time for Vern Cotter to get his ideas across. They got whitewashed in the Six Nations.
Argentina have won just two out of 21 games in the Rugby Championship, but look how they've improved. They started playing heads-up rugby against the three best sides in the world, and they stuck with it despite some big losses.
Then they backed themselves to do it at the World Cup and they blew Ireland away.
They are only going to get better. With so many young players, I see them as absolute contenders to win the next World Cup.
Northern Hemisphere teams can take encouragement in how quickly the Pumas have completely changed their game and started winning.