http://www.natbiogroup.com/docs/education/lubricity%20additive%20study%20results.pdf
I wonder if these folks would do an oil study or have one on hand for engine oil. I know it would answer a lot of questions for everyone.
Don't know if this helps but I found an independent study searching through google. Does anyone have any independent oil studies?
http://www.turbodieselregister.com/TDR57_Oil.pdf