That is defo a sign of TLC! In those days Mobil 1 was silly money, as were synthetics from Agip, Shell & Motul. Proper top shelf stuff when you're a hard up teenager finding your way in the car world. I remember a gallon of Castrol GTX being about £20 back then, and Mobil 1 was £50....for 4 litres! I'm glad they stopped with the stupid US gallon sizing over here.
I had a beater of an old MK1 Jetta 1.5 CL in 1990. It used to drink GTX for fun, so I tried a bottle of Mobil 1 15W50 Motorsport, which was a LOT of money.....back when a gallon of 5 star petrol was £1.89. I bet no one on here remembers 2 - 5 star leaded fuel?!
The Mobil oil completely stopped the oil consumption. I've been hooked on it ever since
There are plenty of other good oils around now though, it's a proper buyers market these days