Four years ago the first-choice 22 were wrapped in cotton wool, with senior players left at home for the summer tour to Argentina and used sparingly in the two warm-up games.
What followed was a dire performance in France, with a team that had self-proclaimed ambitions of winning the World Cup unable to progress beyond the group stage.
Mindful of the need to ensure players are match fit before their opener against the United States on September 11, five warm-up fixtures have been arranged in preparation for New Zealand.
The games begin against Scotland at Murrayfield on Saturday and Leamy believes they are essential.
"We prepared really well in 2007," he said.
"We had a great pre-season and were in really great shape. We just weren't battle-hardened enough in terms of matches.
"Before I'd played my first game in 2007, I'd been on the pitch for possibly 30 minutes.
"With the number of warm-up games we have, lads could have possibly three to four matches played this time.
"For me the big difference this year is that when the first ball is kicked against the USA, the boys will be battle-hardened and up to speed in match fitness.
"The pre-season training has been difficult, but getting match fit is completely different to anything else.
"We probably didn't play too many warm-up games in 2007 out of concern for injury.
"Geordan Murphy didn't make the 2003 World Cup because of an injury and it's a difficult balance to strike. Injury is a risk."
Leamy reckons further lessons have been learned from the ill-fated month in France four years ago.
Declarations that Ireland want to win the World Cup have been placed off limits, while this time the team will also be moving around New Zealand.
In 2007 they were confined to one base camp at an isolated and uninspiring hotel in Bordeaux and cabin fever quickly set in.
"We're better off moving on from 2007 because it was so disappointing," said Leamy.
"There was a such a big build-up and it didn't help that we openly stated we want to reach the semis and final.
"When that didn't happen it was used as a stick to beat us with.
"This time it's all about getting out of our pool. We can start to dream from there.
"It will help moving around this time - it will be nice to have a change in scenery.
"Being based in Bordeaux in that hotel for the duration was difficult."
The arrival of Saturday's trip to Edinburgh signals the end of the gruelling fitness training that opens the build-up to every World Cup.
"The last few weeks have been very intense. It's been pretty exhausting and any spare minute you have, you put up your feet, relax and take it easy," said Leamy.
"You enjoy this time in a sick way. It's a challenge and you have to try to get through the pain. Your muscles are aching and screeching at you to stop.
"It's a good test of your mental strength and it's satisfying when you come out the other end.
"It's very tough. We've had some really tough sessions with guys spewing up their dinners and stuff like that."
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