"The Rugby Championship was a learning curve for us and we've worked on and corrected a number of things from what we learned. That's what we did in Durban [at the camp] for five weeks," said Pietersen.
The big wing is also looking to regain his best form after an indifferent few years, when he struggled with injury and was used in the centres as well. He's hoping to reach the standards he set during the 2007 World Cup, when South Africa went all the way and lifted the trophy.
"In 2007 I was still young and there was a lot of excitement. In 2011 I knew more about what was expected, but I wasn't at my best and this year I know myself even better.
"Maybe the people will talk about the JP Pietersen of 2015 afterwards and not the JP of 2007 anymore.
"I can't wait to get there. We've trained hard ... so I'm feeling really good. We've got a great squad; there's lots of experience, but there are also youngsters so the blend is just right.
"Like the coach said to us the other day, if everything goes well, we'll see the best rugby South Africa have ever played at a World Cup."
Pietersen could well have rookies Damian de Allende and Jesse Kriel on his inside in the early games and Willie le Roux at the back as well, so his experience could be crucial. He knows South Africa are expecting big things from him and the team.
"There are a lot of people out there who look up to us. We have a responsibility to win and we'll be trying to do that. Our goal is to go out there and make this nation proud again."