I was polite, I wanted to know if you really believed that there were no additives in supermarket fuel which you have not answered. Have you perhaps confused my posting with Root-Toot who spoke of 'total nonsense!"
I am not disputing that some additives in premium fuels which may not be present in supermarket fuel bring benefits and many say that they get better MPG which covers the extra cost, I am not disagreeing with or challenging anything, I simply wanted to know if you genuinely believe that there are no, zero, none, additives in supermarket fuel or had just expressed yourself incorrectly.
I recall when fuel, supermarket or otherwise had no additives apart from lead and made my (2nd) living decoking engines, replacing rotten exhausts, changing filthy congealed sump oil etc, then they started adding detergent additives to all fuels including supermarket fuels and I have never had to decoke an engine or grind in valves ever since,(racecars aside) it was late 80's perhaps early 90's.
My pal worked for a nationwide company supplying fuel pumps & forecourt equipment and another delivered fuel from the refineries, all the fuels had additive packages, the premium fuels had different ones that they made big claims for but a lot of what they claimed was in the basic additive package anyway, they may have had higher percentages of some and different versions of others, they don't publish what they are.