Dave Grohl told me once that Nirvana was, at the most, a really bad James Gang. I thought that was a fantastic compliment. When the Foo Fighters were making that series [Sonic Highways], they were doing the episode about L.A. and they asked me to play on this song. They said to just do something in the middle and gave me free rein. I did and it worked out really good. So now I'm like an alumni Foo Fighter.