[tabora]

This is where someone will tell me they feel it's not safe to go 12,000 miles on oil because of some random reason

My 2004 BMW 325xi Touring is at 270,000 miles on 15,500 mile oil change intervals. My 2013 BMW X5 is at 130,000 on the same intervals. BMW LongLife rated oil FTW.

 

[tabora]

Here is a great video on oil: Modern Marvels: The Secrets of Oil (S15, E25)
The discussion of viscosity index improvers is at about 24:55...