The Blues endured a rare trophyless campaign in 2010-11, with manager Carlo Ancelotti paying the price for their failure on all four fronts.
Despite starting and ending the season strongly, Chelsea were unable to recover from a mid-term slump which saw them embark on their worst run in the Barclays Premier League for almost 15 years.
Everyone appeared to have an opinion on the reasons behind the malaise, from injuries, to the loss of experienced players, to the sacking of assistant manager Ray Wilkins.
So concerned were the squad about what Ancelotti repeatedly branded the "bad moment" that they held talks to discuss it towards the end of last season.
And although Terry refused to reveal the verdict they had arrived at, he insisted on Thursday it was one which would prevent history repeating itself under new boss Andre Villas-Boas.
"If ever that does arise again, we can snap out of that really quickly," said the England captain, speaking at the launch of the 20th Premier League season.
"The sign of a true champion is to bounce back if we do suffer a defeat and get together and pull together.
"I think we realised where we went wrong. That stays private between us.
"You're going to lose games throughout the season - it's how you deal with it."
Despite their slump, Chelsea went close to completing the greatest comeback in Premier League history last season.
But Terry acknowledged they had ultimately surrendered their title to Manchester United.
"We lost points against teams we maybe should have beaten," added the 30-year-old, who got within touching distance of the Premier League trophy today.
"Seeing the trophy without the blue-and-white ribbons on, it hurts, it really does.
"I'm really optimistic about this year and I think if we play at our best consistently, which we didn't do last year, we stand a real chance."
As well as the increased threat of Manchester City and Liverpool domestically, Chelsea's Champions League ambitions are in danger of being thwarted by the dominance of Barcelona.
Terry insisted the Catalans were not invincible.
"If you catch them on their day when they're playing as well as they can do, I'm not too sure anyone can touch them if I'm honest," he said.
"But, physically, I really believe that we are a good match for them.
"So, if we come across them early or later on in the Champions League, I believe, out of all the teams, we've got as good a chance as any."
Despite their attempts to prise Luka Modric from Tottenham, Chelsea have yet to recruit a big-name player this summer and Terry admitted it would be "tougher" to win silverware this season than last.
But he insisted he and his veteran team-mates still had the ability and the hunger to win things, and also fight for their places in the side.
Villas-Boas' team selection for Sunday's Premier League opener at Stoke is eagerly anticipated and although Terry appears a certain starter, the Blues captain is taking nothing for granted.
Terry was famously one of Jose Mourinho's "untouchables" but admitted he began to fret last season that he could be axed.
The summer arrival of Villas-Boas has compounded that uncertainty for the defender, who has been the backbone of his side for almost a decade.
"I feared losing my place last year and many other things," said Terry.
"It's a fresh start for everyone, we've had to come in and prove ourselves, even though he watched every game last year and he knows a lot of the players anyway.
"He said anyone can lose their place.
"We all come in fighting for our places so we're all keen to see what the starting XI is going to be against Stoke."
Terry admitted he, Frank Lampard and Didier Drogba were no longer "untouchables".
Insisting he would never "sulk" if he was dropped, Terry said: "I know there's this feeling out there that players like myself, Lamps and Didier, the players that have been there for a long time, take our place in the team for granted.
"But it's the complete opposite.
"We are the ones day in, day out, who are digging in deep, getting everyone together, making sure we are setting the example.
"And when we play a five-a-side, it's the players like me, Diddler, Lamps and Ash (Ashley Cole) who care and say, 'It's not okay to lose 3-0 in training'.
"If you lose 3-0 in training then you go into the game at the weekend not believing, and for us that really matters.
"So when people say, 'We've been here a long time, we don't really care' - it's the complete opposite."
Source: Team Talk
Source: Team Talk