"We've got two outstanding No. 10s in Owen Farrell and George Ford, and we want them to keep learning.
"Guys like Andrew Johns, they did touch the ball 50 or 60 times in a game, they had to fix defenders, know when to drift, know when to be straight, know when to take a little unders line, how you use your eyes, where you position your hands.
"For those guys to have that lesson this afternoon is invaluable, they'll remember it for the rest of their life."
Jones said he's even considering hiring Johns, a former Kangaroos captain regarded as one of the greatest playmakers in league history.
"I've always admired his skills as a player, he's got a lot of knowledge, a lot he can teach people, and we've been chatting for a while about the possibility of him even coming in and doing a little bit of work," Jones said.
"So today was the ideal day, we had downtime in training ... I'm not sure about [making him part of the England coaching team], we'll just wait and see."
While England relied on staunch defence to see them home in Melbourne last Saturday to claim a 2-0 series lead, Jones hopes Ford and Farrell can heed Johns' lessons and spark attacking brilliance in Sydney.
"They will have learnt things," Jones said. "Now you learn things, it doesn't always mean you pass the test, but they've definitely learned things."
Johns is not the only Australian helping the old enemy.
Jones himself is an Australian and former Wallabies coach, but since taking charge of England he has recruited former Australian playmaking legend Glen Ella as attack consultant, former Wallabies trainer Dean Benton as head of strength and conditioning, and brought backrow icon George Smith in to mentor his flankers before the series.
The possibility of Johns' helping to mastermind attacking plans that help England claim a 3-0 series win will add salt to already wounded Wallaby fans.
No Wallabies player had been born the last time the side lost a three-Test series at home, but Jones had a dire warning for them.
"We still haven't seen the best of this [England] team, we're on a learning curve and we want to keep improving," Jones said.
"We want to be the best team in the world, to win this series 3-0 would indicate we've got the right to be the second-best team in the world, and then we take it from there."