How Ireland have closed the gap on the superpowers of world rugby

Schmidt’s men boast a level of mutual understanding that is helping them outperform rivals

"We know more than we can tell," wrote scientist-philosopher Michael Polanyi in The Tacit Dimension, published in 1966. The concept of unconscious knowledge has been around for a long time. Tacit Knowledge. Organisational experience. In the context of team sports, former Wallaby prop Ben Darwin, founder of analytics firm Gain Line, calls it cohesion.


Tacit knowledge is, by definition, unobservable. But that doesn’t mean one can’t make estimates.

Darwin says that while England has excellent coaching, seemingly infinite money and great talent, the greatest resource one can possess is the level of understanding between players. “England had a high Test cohesion score in 2003,” said Darwin. “But the main difference was that many other countries were quite low.”It was an opportunity for England that they were able to exploit.

Last week Ian Ritchie, chief executive of the Rugby Football Union, called England's four straight second-place Six Nations finishes unacceptable. Darwin argues that based on the declining levels of cohesion within the England set-up, Lancaster should actually be lauded for his coaching performance over that time.


The data in the accompanying graphic represents each team’s peak cohesion value, as calculated by Gain Line, for each Rugby World Cup since 1999 with a projected value for this year’s tournament .

The lighter part represents each side’s shared experience at Test level; the darker portion the shared experiences that side has enjoyed in the club game.

Darwin says Lancaster is actually overperforming. “The game has changed since the 1990s,” he said. In terms of the inherent cohesion of England’s set-up, “they’re being outstripped by Ireland, Wales, New Zealand, South Africa”, who each have a much smaller number of professional sides at the top level.

Gain Line ranks New Zealand as having the best player talent in the world, with England and South Africa just behind. Ireland and Wales need higher cohesion levels to close that talent gap.

Most important

“People have always thought that experience in general is great,” said Darwin, “but it’s actually [shared experience] that’s the most important.”

In 1999, Wales had nine teams in the Celtic League and an accordingly low domestic cohesion score. When the bulk of their playing talent was eventually compressed into just four teams, the shared experiences between the Welsh Test players increased.

The recent Welsh mini-exodus to other leagues – George North, Jamie Roberts, Richard Hibbard among them – is reducing their cohesion score, something that, according to Darwin, could have repercussions in the future.

Darwin sees the biggest impact of cohesion on defence in particular: how a group performs under duress. Player acquisition too: “Every player is actually a representation of those around them, both in a work environment and a sporting environment,” he said.

“If you buy a player, you need to understand that the other guys aren’t coming with him.”

There has been similar research in the NBA, Australian Rules and football. In general, stability is linked with success.

Keeping a Jamie Heaslip in Ireland has an impact both on the present and the future. See him move somewhere else and while cohesion at Test level might be maintained, the domestic level will fall.

Talent base

A link with the future broken; no more tacit knowledge subconsciously absorbed by a junior player that he can then use on the field when his time comes. “Realistically, the talent base for Ireland and Wales hasn’t changed,” said Darwin, “it’s just how they’re arranged.”

Darwin has been bullish about Ireland’s chances in the 2015 Rugby World Cup, forecasting a run to the final based on high Test and domestic cohesion. One notes that the Irish side of 2007 had even higher cohesion scores. Hopefully for Irish fans the class of 2015 will get a better World Cup grade.