While dyoning the car? That's like tire compaines making 18" drag radials. You use that higher Octane to besafe and get more power. Not like it's cheating or anything. 5-600 to the wheels, is 5-600 to the wheels. It's not like he can use it and no one else can. Can't see the point here. Honestly ( not speaking of you or myself ). But I'm sure 95% of the people around have no clue on just how much power 550+ to the wheels is. Way more than anyone will ever need on the streets........
Another thing, isn't lean due to pressure in fuel not being able to keep up with the boost? Higher the Octane the cooler the fuel right. Thus allowing you to run higher than normal psi on smaller parts ( cc's )?