Hrmm not sure i trust NZ's fuel grading to be able to do that....
Slightly OT but when I got my Evolve tune for the MSS52 they did ask me what grade of fuel I was running, which is 98RON. I see their notes on the tune file sent back are for 91 Octane, not sure if that's the USA AKI measuring though since they have a lot of USA customers.
Aside from fuel grade, carbon buildup on older/higher mileage S series engines would also play a part in pre-ignition/detonation. So knock control at higher loads and rpm would be important. Would it not?