12 months earlier Parks had been Scotland's leading light during the 2010 Six Nations but despite a bright start, the Australian-born 32-year-old has blown hot and cold for the Blues.
Parks, who was also one of Scotland's better performers at the 2007 World Cup, puts that down to a change of environment after seven years at Firhill but he has promised Jackson he will not give up the No.10 shirt without a fight.
"I want to get my starting place back and play a part of the World Cup," Parks told the Scotsman.
"The reason I think I thrived in the last World Cup was because of the carnival atmosphere, all the focus on rugby and the enjoyment of the game, and it remains my greatest memory in rugby.
"That drives me now because, if I get to New Zealand, I'm sure the players will get that carnival feeling again.
"Now my focus can turn to Scotland and learning from all of that. I've got a lot of work to do this summer, on my game and my fitness.
"I've always had a lot of respect for Ruaridh and have tried to help him at different stages of his career. He's done really well and did really well against Italy in the last game of the Six Nations, so has cemented a place there."