What a difference a year makes for Blues
Given the so called strength of the opposition, Leinster produced one of the greatest purple patches in European rugby on Saturday night.
After going 13 points to 5 down against Northampton midway through the first half, Leinster remarkably lead by over 40 points some 30 minutes later.
In the end the rampant Blues scored nine tries to one and sent Northampton packing with their biggest European defeat ever.
At the same time Leinster maintained an unbeaten home record in 2016. More good news followed on Sunday, when Castres defeated Montpellier leaving Leinster five points clear at the top of their pool, what a difference a year makes.
A few years ago Munster and Irish out-half Ronan O'Gara stated that the Irish rugby players were as good if not better than those in the English Premiership.
O'Gara was not being arrogant, that was his honest belief, and over the years he has been proven correct.
Last weekend Munster defeated Leicester while at the same time Leinster accounted for Northampton.
This weekend Connacht beat Premiership high flyers Wasps, while Leinster not only beat Northampton again, they humiliated them.
Forget about Northampton missing some of their key English internationals, they still proved in establishing a 13-5 lead after 20 minutes they had come to play, Leinster were just too clinical and ruthless in everything they did, and this win must go down as one of Leinster's best all-around performances in Europe.
It's hard to put this win into perspective, but Leinster were at times sublime, their forwards, to a man, were powerful and skilful and their backs created space with some excellent passing and width from their backs.
Leinster's new out-half Ross Byrne, who again looked composed, ran the backline well often using the cut out pass to excellent effect and stretch Northampton's defence.
In terms of individual performances young winger Adam Byrne again did well, scoring twice making it seven from the last six games, while all the other backs excelled.
The foundations were built by a superb home display in the forwards, where there Leinster scrum is now one of Europe's best attacking weapons, while Leinster's lineout only coughed up one lost ball all night.
It does not matter who comes on for Leinster in the front-row these days with everybody able to make a serious impact with ball in hand.
Furlong, McGrath, Healy, Tracey, Cronin and others, what options Leo Cullen has open to him in the front row, an area where Leinster struggled a few years ago to even fill the spots.
In fact despite France and England teams not being overly interested in what is happening in the Guinness Pro 12 most of the Pro 12 teams are doing particularly well in their Champions Cup pools.
One hopes that these recent results like that of Leinster, Connacht, Glasgow and other Pro 12 teams will not mean that some of the English teams will now start to react like the French teams over the years. Namely place more importance on their local Championship than in Europe.
Once the sugar daddies that finance some of these clubs in France and England potentially lose interest in European rugby, then Irish rugby will suffer.
We have already seen a trend in some overseas clubs of not fielding at full strength and certainly not risking their No 1 teams in Europe, instead bowing out far too early especially if they feel they have a battle just to qualify.
That's why it's actually an advantage to have the big name teams still in this competition. But that is then and this is now.
When Leo Cullen first looked at the European draw at the start of this year, he would have known that the two weeks prior to Christmas would probably define how far Leinster would go in this year's Champions Cup.
Cullen need not have been so worried, Leinster simply had too much power and pace for an English team that is now in serious need of repair.
The sight of some of the Northampton supporters leaving the game early in embarrassment told the full story, they would have booked their tickets at the start of the season, but with a quarter of the match to go probably preferred the craic in town rather than watch a rampant Leinster inflict more misery.
The large margin of victory was important should the pool come down to tries scores or aggregate points difference but it's hard to see two teams ending on equal points now.
I know it's tempting fate with so much more rugby to be played, but to qualify as top of their pool would be a major achievement from where Leinster wer this time last year, and a further indication of the strength in depth in Leinster rugby.
Last Christmas Leinster head coach Cullen's turkey had a sour taste to it, this year he will tuck in with gusto and boy does he deserve it.
A fantastic win.
It's hard to put this win into perspective, but Leinster were at times sublime