I can answer this question, I used to work at Safety-Kleen, the worlds largest waste oil re-refiner, Super Tech oil is re-refined oil from Safety-Kleen systems, their facility is near Chicago, all of the collected waste oil gets shipped there where it is distilled.
Once distilled all that is left is 100% clean pure base stock, which is then sold, additives added and made back into brand new motor oil.
Full synthetics get the synthetic additives, dino juice gets the dino additives, viscosity modifiers etc.
All oils are of the same base stock, ATF, gear oil and motor oil. Safety-Kleen does sell their branded lubricating oils, which the US military uses, my oldest son is a mechanic in the Army and confirmed this for me.
The only difference between Super Tech and other oils is the quality of the additive packages and the name on the bottle.
The base stock never ever wears out, it is only the additive's that wear out,
This is true for all oils and coolants.
The additives wear out and the base stock gets contaminated, replenish the additives and clean the base stock and it is as good as new.
Pretty cool stuff.