That's just covering all the variables that are current. I had a GT86 hire car in Japan with the 16's and smaller brakes. 17x7 is for stock and 17 x7.5 is PP.
Interesting... I just looked this up in my manual.
I have blue series with performance pack.
This is from my manual lol... so it doesn't make it clear at all. It has 3 sizes listed... fun.