"It took a while to break Italy down but we made them work hard and then took our chances well. It's probably phase one, we wanted to get out of the pool because it was a big thing for us.
"It was an all or nothing game for us here, a final for us, and we're just glad to be out of the pool."
The interplay and creation of those three second half tries were pleasing factors for the coaches, with Tommy Bowe, Gordon D'Arcy and replacement Andrew Trimble all making breaks in the build-up to the scores.
Kidney added: "The first half was pretty nip and tuck and it always is in Ireland-Italy matches. It's a case of taking the breaks when they come your way. Tommy got his bit of an opening and we finished it well, and that gave us a bit of daylight."
The Corkman again thanked the huge numbers of Ireland fans who turned out for the final pool game, making reference to the fact that many of them are now living and working in this part of the world.
"Times are different in Ireland economically. A lot of these people have had to emigrate. The fact that they've come out tonight to support us, we're just so happy for them that they're having a good night out."
The victory - the 23rd of Kidney's coaching reign - rubberstamped Ireland as winners of Pool C on 17 points, with Australia, two points behind, also qualifying for the quarter-finals.
Wales, who finished second in Pool D behind South Africa, will provide the quarter-final opposition for Ireland in Wellington next Saturday.
It is a match that two of the form teams in the tournament will be relishing. When they met in Cardiff last March, Mike Phillips' controversial try helped the Welsh take a 19-13 victory.
But Ireland have won nine of the sides' last 12 meetings, stretching back to 2001, and have plenty of momentum following their triumphs in New Plymouth, Auckland, Rotorua and Dunedin.
"We've got ourselves into a place where we're playing Wales for a semi-final place and that's all you could hope for at this stage," added Kidney.
"It will be like a Six Nations game because the players know each other so well, space will be cut down. It will be like a cup final gaine.
"That's what this competition is all about. Today was a cup final and thankfully we've qualified for another one."
Given the respect he holds him in, Kidney made sure to share some words of consolation with departing Italy head coach Nick Mallett who is bowing out after four years at the helm.
"I think Nick's record speaks for itself. Any of the lads will tell you it (the Italy match) is one of the tightest games in the Six Nations.
"Nick's been a big part of that. I've been lucky to meet him at coaches' meetings and he's an excellent rugby man."
Mallett, who previously coached the Springboks, clearly appreciated the pitchside chat. "I was incredibly touched by what Declan Kidney said to me at the end," he explained.
"He's an amazing gentleman and rugby is very privileged to have men like him running national sides. To have another coach say the things he did was very touching."
Asked what he made of Ireland's chances of progressing in the knockout stages, the South African replied: "I don't think any team would be confident of playing Ireland at the moment.
"Where's their weakness? Ireland are more than capable of knocking out every side left in their half of the draw.
"Wales are playing very good rugby, they were close to beating South Africa. But my view is that this Irish side have targeted Australia, they have targeted us and when they're playing like that, they're very hard to stop."
Follow the Ireland team in New Zealand on www.twitter.com/irfurugby.