Argentina defence coach Pablo Bouza believes his side would have struggled to reach the World Cup semi-finals had they joined the Six Nations instead of the Rugby Championship.
The Pumas' push for Six Nations inclusion, to play matches in San Sebastian in Spain, was dismissed out of hand by tournament organisers.
Argentina instead joined New Zealand, Australia and South Africa's annual battle, the Tri Nations reborn as the Rugby Championship in 2012.
For the first time no northern hemisphere nations have reached the World Cup's last-four stage, Argentina thumping Ireland 43-20 in the quarter-finals, with Bouza admitting regular clashes with the best in the south have paid great dividend.
When asked if Argentina would be as strong now had they joined the Six Nations in 2012 and not the Rugby Championship, Bouza said: "I cannot be sure, but I don't think so, they are quite different styles.
"Last year when we finished playing the championships, we struggled, we came back here and we lost against Scotland.
"But they are such different styles, when you play here in autumn, November, the pitches are slow, the breakdown is tough, it's tough to have quick ball to play.
"When you have quick ball, for us it's very positive. I think playing in the Rugby Championship for us has been great. The players used to play against New Zealand far less frequently.
"Before you would play them every six or seven years, and now they have played 10 matches against them in four years.
"For the players, and for us as coaches, we are always learning when they play against New Zealand. So the Rugby Championship has been something great for us."
Argentina's ebullient run to a second World Cup semi-final in eight years has captured the country's imagination, with the victory over Ireland knocking football off the back pages.
The Pumas will now face Australia at Twickenham in Sunday's semi-final - on the same day the Argentinian people go to the polls to elect a new president.
New Zealand's 2011 World Cup-winning coach Graham Henry took a consultancy role with Argentina when the Pumas joined the Rugby Championship, helping boss Daniel Hourcade usher in a new attacking blueprint.
Now that fearless approach has yielded huge reward, the Pumas relishing taking risks and lighting up the often-prosaic Test arena.
Former Harlequins and Leeds back-row forward Bouza has worked in tandem with Hourcade, ensuring the Pumas continue to balance their new-found freedom with their traditional scrum and pack strengths.
Argentina ran in two tries inside the first 10 minutes against Ireland on Sunday against Joe Schmidt's shocked men - and Bouza hailed the victory as among the finest under boss Hourcade.
"I think it was one of the best performances Argentina have had with Daniel as coach," Bouza said.
"The first 20 minutes was great, then we had the yellow card and Ireland came back with great power. The last 20 minutes when our bench came on it was great for us. But Australia will be extremely tough.
"It's hard to defend their attack because they have so many different styles.
"They can play with an open style, or through the centre, so it's going to be very, very tough for us."