Ireland's position as the strongest of the home unions was confirmed when they finished RBS 6 Nations runners-up.

However, the rebirth of old frailties indicates the gap could be narrowing.

The tournament as a whole suffered from the staging of the pivotal showdown between Ireland and France in only the second week, effectively settling the title after just two games.

But greater damage was done to Irish belief that they have sledded their suspect temperament during the big occasion.

They were thumped out of sight by their successors as Grand Slam champions, exposing a gulf in class that could have worrying repercussions for next year's World Cup.

Stephen Ferris, Ulster's ferocious blindside flanker, revealed on Saturday that Ireland are already gearing up for New Zealand and though they will never admit it in public, a semi-final spot is the target.

But events at the Stade de France evoked memories of the 2007 World Cup, when they flopped horribly, and previous near-misses during successive failed attempts to win the Six Nations.

A courageous victory over England gave the impression that ghastly evening in Paris was just an aberration, yet a shattering defeat to Scotland on Saturday suggests otherwise.

Man for man there should have been no contest, yet amid mounting pressure to sign off their four-year tenancy at Croke Park in champagne style and lift a fifth Triple Crown in seven years, they suffered a demoralising setback that left management and players visibly shaken.

Only the most loyal of supporters would back Ireland against one of the heavyweights in the quarter or semi-finals of the World Cup.

Defenders will point to their Grand Slam and to last autumn's heroic victory over South Africa as evidence of a team that has discovered how to win big games.

But opponents would argue they made heavy weather of the clean sweep, while an exhausted Springbok side looked ripe for picking.

France aside, Ireland remain the most formidable team in Europe even though it is not too fanciful to suggest Scotland could have finished in second place.

The Scots were magnificent at Croke Park, capitalising on an over confident gameplan by Ireland that bordered on the arrogant, and should also have beaten England, Italy and Wales.

Andy Robinson's presence at Murrayfield has clearly had a galvanising effect, even if their results were cruel, and Scotland may be ready to start punching above their weight once more.

There is a feeling England could prove useful if they get their selection and attitude right, yet that is big if under manager Martin Johnson whose innate conservatism acts as a straightjacket on all fronts.

Psychologically-flawed Wales had their moments and will continue to do so, amazing and frustrating in equal measure as the Six Nations' great enigma.

For the moment, however, it is Ireland who continue to gaze down upon their rivals from the home unions.

How much longer the status quo will be preserved remains to be seen and it is undeniable that Kidney now faces challenging questions.

Some of the old guard - starting with John Hayes but including Paul O'Connell and David Wallace - have doubts hanging over them.

The once-indestructible Hayes is creaking after his decade of unwavering service and must be replaced, O'Connell has endured a poor Six Nations and whether there is another 18 months of Test duty in the superb Wallace is uncertain.

For all his talk of squad development, Kidney relies heavily on much of the pack that served under Eddie O'Sullivan.

Behind the scrum he must select Jonathan Sexton at fly-half and only introduce Ronan O'Gara as an injury replacement, allowing the gifted rising Leinster star to develop his confidence and his game.

Brian O'Driscoll had a quiet championship, though only a fool would start writing the enduringly-brilliant captain's obituary 18 months out from the World Cup.

Ireland rely so heavily on their talismen, namely O'Driscoll but also O'Connell, and when they fire so does the team.

Perhaps both are suffering a post-Lions hangover and at times during this year's Six Nations it has been the younger players who have been carrying the side - Tommy Bowe, Keith Earls, Jamie Heaslip and Ferris.

Since 2004 Ireland have enjoyed the most decorated spell of their history, consisting of four Triple Crowns, a Grand Slam and Heineken Cup titles for Munster and Leinster.

It is boom time for a country that has produced some spectacular rugby, bringing colour and excitement to the Six Nations.

But for all that success, it is perhaps the next 18 months culminating in the World Cup that will determine just how good this team really is.