At the midpoint of the season, the expansion sides have managed just two wins between them and been subjected to some humiliating losses.
The Jaguares, Argentina's first team in the competition, have laboured to a single win, as have South Africa's Southern Kings, who rejoined the tournament after playing a single season in 2013.
Japan's debutant Sunwolves are yet to toast victory, however, and at the end of their first tour of South Africa they were destroyed 92-17 by the Cheetahs on Friday, a result labelled “embarrassing” for the competition by rugby pundits.
The Tokyo-based side, thrown together at the last minute, were always expected to toil in the world's toughest rugby championship, where a brutal travel regime tests even the southern hemisphere's most seasoned combatants.
Expectations for the Kings were also downplayed after their preparations were derailed by financial turmoil in the months leading up to the season.
More was expected of the Jaguares, who boast a roster of Argentina internationals and were tipped to challenge for the Africa 2 conference and win a playoff spot in their first season.
However, they were trounced by the Crusaders on Friday and have lost six straight games since their away win over the Cheetahs in the season-opener.
Expansion to 18 from 15 teams has opened new markets and boosted broadcasting revenues, but at the same time it has raised fears that the tournament has spread itself too thin and become too confusing for the casual viewer.
“I watch most of the games but some of the games put me to sleep,” England coach Eddie Jones told Australian media in a recent interview.
“I don't think the standard's great this year. Having 18 teams in the competition, it's really dropped the standards.”
Pundits have grumbled for years that Australia, who have five Super Rugby teams, and South Africa, who now have six, lack the playing stocks to be competitive.
Australia's fourth team Western Force, who joined the competition in 2006, have never reached the playoffs in 10 seasons and the Perth side are all but condemned to missing out once again this year.
The Rebels, who joined in 2011, have also never made the post season, while costing private owners and the Australian Rugby Union millions of dollars in losses.
In contrast to Australia and South Africa's struggles, New Zealand has flourished with four of the conference's five teams winning 13 championships between them since the tournament's 1996 debut.
The latest expansion has only entrenched New Zealand's dominance of a lopsided competition as smaller talent pools in Australia and South Africa are spread even thinner.
Four of New Zealand's five teams currently occupy playoff spots from the Australasian Group, while the ACT Brumbies look like being Australia's sole representatives in the postseason.
“Outside of the cracking New Zealand conference, the competition appears to be decidedly average,” New Zealand rugby writer March Hinton said in a column over the weekend.
“Spreading the good word of rugby is important, and they are clearly eyeing revenue opportunities. But our flagship franchise competition must never become Stupor Rugby.”
Original source: Super Rugby expansion questioned