Mitchell also reiterated there was no chance of him resigning after New Zealand's failure to reach the final.
He maintained there was nothing he would have changed about their preparation.
"The key area was that we lacked maturity in the semi-final," he said. "We are very young and maybe I underestimated that area. But when this group mature they'll be even better. I didn't make any mistakes with the selection of the squad.
"Sometimes teams have to go through these experiences and if this group remain together it will hold them in good stead. England had the same experience in 1999 in the quarter-final and many teams learn from experience."
Mitchell insisted the All Blacks would persevere with their attacking, running style which has brought 81 tries in 2003, six of them today when wing Doug Howlett and fullback Mils Muliaina scored their seventh touchdowns of the tournament to become the World Cup's joint-leading try scorers.
They were joined on the scoresheet by second-row Chris Jack, young wing Joe Rokocoko, Brad Thorn and Marty Holah with Pepito Elhorga grabbing France's consolation try. They were just about the only notes of worth from a match which saw New Zealand return to the Telstra Stadium, scene of their semi-final grief against Australia, and for France, their rain-lashed defeat against England.
Considering the All Blacks had also missed out on a £35,000 bonus per man it was hardly surprising the match lacked intensity with both sides going through the motions before a crowd of 62,712, many of them streaming home 10 minutes before the final whistle. Coach Bernard Laporte made 13 changes to his side, hoping to herald a new chapter in French rugby en route to the French-hosted 2007 World Cup while New Zealand made just one switch in their starting line-up scrum-half Steve Devine in for the injured Justin Marshall.
But the match had an exhibition air with little edge and while France held New Zealand to a 14-6 lead at half-time it was only a matter of time before the All Blacks' class told.
Laporte later insisted he had no regrets and was proud of his side's fourth-placed position.
"We have to admit the supremacy of the All Blacks tonight," he said. "But we have had a good World Cup, made the semi-finals and played some good rugby along the way. Many people would have loved to have been in our position.
"We could have beaten England but there is a certain fragility in the French game at times. Now we can move forward to be a force in the Six Nations."
One omen for England: in all previous World Cups the eventual winners and the team which finished third have come from the same semi-final.
Just another obstacle for Clive Woodward to overcome on Saturday.
NEW ZEALAND: Muliaina, Howlett, MacDonald, Mauger, Rokocoko, Spencer, Devine, Hewett, Mealamu, Somerville, Jack, Williams, Thorne, McCaw, Collins, Carter.
Replacements: Carter for MacDonald (18), Hammett for Hewett (71), Hoeft for Mealamu (71), Thorn for Williams (50), Holah for Collins (44), Ralph for Carter (75). Not Used: Kelleher.
FRANCE: Poitrenaud, Elhorga, Marsh, Traille, Bory, Merceron, Yachvili, Marconnet, Bru, Poux, Auradou, Privat, Tabacco, Chabal, Labit.
Replacements: Brusque for Poitrenaud (26), Liebenberg for Marsh (40), Michalak for Merceron (65), Ibanez for Bru (54), Crenca for Poux (40), Pelous for Privat (40), Magne for Tabacco (57).
Referee: Chris White (England).