The former spinner was a member of the England team when Pietersen made his debut, and Giles believes that their history will help the current side.
"Kevin is an incredible player," former Warwickshire coach told Sky Sports News. "He's got a great record and I've already managed him in India. He did pretty well over there.
"We got on well when we played together. There's a danger of it being awkward [now] and I think for the first week it is a little bit because we do know each other pretty well, but surely there is always a line of respect there.
"I think it's advantageous because I know him very well, so hopefully I know what makes him tick and he respects me."
Pietersen has been rested for the current one-day series with New Zealand.