Between the third minute and the 38th at Franklin's Gardens on Friday night, you could have been forgiven for thinking Saints had accidentally stumbled into an Alliance Cup final.
Because so quick and strong were the black, green and gold that they made the opposition look like a part-time outfit.
After going 3-0 up through a Marcus Smith penalty, Quins suddenly found themselves submerged.
And after drowning under the pressure, they had shipped four tries, conceding a bonus point before the break.
Saints, through the artistry of men such as James Grayson and Rory Hutchinson, found openings, and they finished the job through the power of Taqele Naiyaravoro.
The behemoth wing was at his brilliant, unstoppable best, brushing off defenders like they were cobwebs.
At times last season, and so often in the early stages of this one, watching Naiyaravoro has been worth the entrance fee alone.
When at his brutal best, he is one of the most entertaining players around.
And that was the case again here as he put his team in a hugely dominant position just before half-time.
To Quins' credit, they kept fighting, pulling a score back before the break and another soon after the restart.
Saints, with the bonus point in the bag, lost their intensity and their attacking vigour, until a second try from skipper Teimana Harrison put the win beyond doubt.
It was a third in as many matches this season and while not every minute has been pretty, Saints have been pretty effective overall.
They have shown different ways to win games, refusing to buckle when things have got tough.
They went behind late on at Saracens before turning things around, and they were down at half-time against Worcester before blowing the Warriors away.
This time, they reacted when it looked like Quins might just give themselves a sniff at 27-15 down in the second half.
A huge positive is that Saints have not only shown the swagger they displayed so often during the second half of last season, they have had the steel to match.
Against Quins, the backs tore things up before the forwards turned up the heat to earn a popular try for Mike Haywood.
Saints showed how both sides of their game have developed during the summer, and they sit at the Premiership summit because of it.
But there will be no getting carried away.
Things will keep ramping up as players return from the World Cup and Europe's best begin to fight it out in the Champions Cup.
The Saints coaches have been keen to avoid too much back patting during the early part of this season, instead demanding weekly improvements.
That is what they have to do, and it has worked well so far.
Saints are on an upward curve, and if they can continue that pattern at Bath next Saturday, they will go into the Champions Cup in the best possible shape.
And that is exactly the condition they will need to be in when they return to the continent's top table.