Winning Blues coach Pat Lam harked back to the four successive losses his side had as central to overcoming the Waratahs 26-13 in their playoffs game at Eden Park on Friday.
The Blues only stopped the rot last week when beating the Highlanders, but Lam said the lessons from the loss were a weapon in subduing the Waratahs.
"Things that happened out there in the four losses we had, a lot of lessons and things we didn't quite do right before, as a coach it was just so pleasing to see them tidy things up there and emphasise the learning that has happened from those games," Lam said.
"I know everyone thought we were imploding from the four losses but your team culture, systems and structures have to be tested as you go through and it doesn't get tested at nine games undefeated."
"It gets tested under four losses and that's where you get the growth and that's what I saw out there today which was pleasing."
That had had been seen at the end of the first quarter when the senior players had sorted their problems out, and Lam said he hadn't needed to send any messages onto the field because he could hear through his messengers' microphones that the players were talking about sorting the problems.
One concern from the win is the likely absence of lock Anthony Boric for next week's semi-final after he suffered a foot injury late in the game.
Lam said the next 48 hours would determined the extent of his injury but he felt he would be unavailable, the seventh Blues lock to suffer injury this season.
It was likely that Chris Lowrey would be drafted in as a lock in the semi-final.
Lam said the excitement of playing in the first finals for eight years had resulted in the side making a shaky start due to nerves.
Missed tackles meant the Waratahs had a lot of early possession but a half-time decision to look after the ball had proved effective.
Captain Keven Mealamu said: "We're really happy with the way we're going at the moment."
"There was a lot of emotion during the week and that's probably why we didn't get off to as good a start as we would have liked. But after 20 minutes we got back into our work and I was really happy with the team."
Mealamu noted the role lock Ali Williams had played with the side after being out for two seasons with successive Achilles tendon injuries.
"We've seen him really grow with the team and get his confidence back which takes a little while," he said.
"It's just good to see him back on his feet and bringing excitement back into the team."
Lam added that Williams' advance at the pressure end of the season was not by chance, fluke or accident.
"It was by choice. The choice he made was he going to continue playing this game and was he going to come back after the setbacks he's had," he said.
"At the end of training he does so much work after the teamwork on his own game."
"He's driven and for any coach it is easy to have a player who is driven than a guy who might have a lot of talent he is trying to push along. It doesn't surprise us at all how he's coming along."