Some will say they foresaw what transpired in Lansdowne Road on Saturday. The European champions' form this season has been up and down; the cutting edge that made Leinster such box office on their march to glory, has been lacking.
A tally of just three tries in four Heineken Cup games suggests a squad with a problem, although they have only conceded three.
Only Edinburgh of the 24 teams involved have scored fewer tries.
Even Italian minnows Treviso and Zebre, despite not recording a single win between them, have scored five tries apiece.
Leinster have fared better in the Pro12, crossing the whitewash 29 times in 10 games, but that hitherto rock-solid defence has conceded 25 tries.
Overall, they have suffered five defeats in 14 competitive games.
The stats don't lie. Leinster are where they are because they're simply not playing well enough.
And yet in the two biggest games of consequence before Saturday, against Munster immediately prior to Round 1 and again at Clermont last week, they managed to raise the level of intensity close to the standard required.
Now we know that those performances flattered to deceive. Leinster were out-thought and out-fought by the hungrier, more athletic, more skilful side on Saturday.
Often in the opening minutes, body language can reveal a team's mood, and at the Aviva, Clermont took the game to a home team that was operating in a mental comfort-zone – Northampton did the same to Ulster at Ravenhill immediately afterwards.
The top two inches are still the most important in this most physical of games.
In Dublin, the difference in line speed or lack of any recognisable rush defence (with which Leinster have become synonymous) paved the way for Clermont to bully the breakdown and tackle areas.
And bully is not too strong a word. Leinster have earned plaudits for their all-encompassing brilliance in recent times but on Saturday, in perhaps their biggest game of the season so far, the fundamentals went missing.
Some 46,000 home fans expected Leinster to set the tempo but instead it was Morgan Parra, Wesley Fofana, Aurelien Rougerie and the French cast of stars who dictated the pace.
The win was the least they deserved with the final margin flattering Leinster.
Credit Jonny Sexton and Fergus McFadden for the try which secured a bonus point, but it wasn't the bonus they were hoping for.
No doubt the hindsight experts will be now out in force. But on the evidence of last week's game, I did not see this collapse coming. Save for a dicky line-out in the final quarter, the signs of distress were most definitely not there.
And one of Joe Schmidt's comments afterwards added to the mild depression.
"I don't think we have the same depth as some of the big-spending French clubs," he said.
It was out of character for the Leinster coach, but still smacks of sour grapes.
Strange how "strength in depth" wasn't an issue following the Bordeaux semi-final success over the same opposition last season.
Far more gracious was Mark Anscombe's summation following Ulster's first defeat since he took control. "It's sad because it's our first loss, but we got beaten by a better team," he admitted.
That has a touch of class. I am a big admirer of Schmidt, and he can be forgiven, but given what happened last week, it's pertinent to ask the question: how do you think Eric Elwood feels, Joe?
A bad end to a bad day for Irish rugby.