[Rajmun340]

the listing gives a clue
"1 owner no accidents adult woman driver lived in wine country and worked in orange county"

If she lived in Napa county and worked in Orange County that is 400-450 miles commute one way, 800 miles round trip. Probably bought the car with those big weekend commutes in mind. Over 7 years it computes to ~ 268,800 ! (assuming 48 work weeks / year).

Every week this engine saw two 5-7 hours of pure highway commutes.
This would have perfectly guaranteed that all ethanol dilution in the oil got burned away. Some people might not agree with where i am going with this but you cannot take that away: engine ran 268k miles with no fuel dilution of the oil by virtue of how it was used.

If you do short trips, sit in traffic and do not run the car for long duration bouts it will accumulate substantial fuel (+ethanol) in the oil between oil changes. That is not debatable. (No, Blackstone told me they cannot detect ethanol directly in the oil if you wondered)

This by itself does not prove anything. Highway miles are the best miles for any car. But added to other research it supports my RB Fail theory.