My trust in Mobil 1 has been somewhat diminished with all these marketing changes lately. I did find this in reference to the "3 synthetic fluids" in the tri-synthetic formulation.
http://www.swedishbricks.net/700900FAQ/Fuel-LubricantData1.html#Synthetic%20Oil%20Notes
Here's another question, was the addition of this super-syn necessary to meet the SL standards and the customer's standards?
Darryl