I'm not an expert but I've been taught by experts. Back in flight school the piston engine instructor explained what all the octane stuff meant and I've forgotten most of it. One thing I do remember was that the octane rating is for measuring gasoline's resistance to preignition or predetonation. Simply put, the ability to not spontaneously explode due to heat and pressure during the compression stroke prior to the spark plug firing. The higher the compression and operating temperature of the engine the higher the octane required to prevent preignition of the fuel/air mixture. Being a typical considerate Navy instructor he asked us all what we put in our cars. When we answered he told us that any octane rating above what was required to prevent pinging was a complete waste of money but that the oil companies loved us because we increased their profits by paying for octane we didn't need, rather like buying 11 gallons of gas to put into a 10 gallon tank and pouring the last gallon on the ground. I've always tried to get by on only what was really necessary ever since.

We all like to think of ourselves as rugged individualists. But when push comes to shove most of us are sheep who do what we are told. Worst of all, a lot of us become unpaid agents of whoever is controlling the agenda by enforcing the current dogma on the few rugged individualists who actually exist.