The Boycott Castrol debate has prompted numerous posts regarding (and requesting)... data ...science...performance. Uoa's seem to be one of the only unbiased indicators of true "performance" out there, aside from the oil makers secret labs...! It just seems like the number of variables that can contribute to a UOA's final result are mindboggling!!! Consider this brief list: Engine type: High revving? Oil capacity? Chain,gear,belt driven cams? Overhead cams? Air Filter? Oil Filter? etc...!!! Driver: Lead foot; or baby it all the time? Idle time? Highway or stop and go? Duration of trips? Location: Cold winters? Hot summers? You get the point...it seems it would be just about impossible to compare apples to apples regarding oil quality and longevity. Case in point: My engine is a firmly driven 1.8l four cylinder, dohc, that spends a good deal of time above 5000rpm. My Dad's engine is a classic 5.7l pushrod V8(I'm Canadian...I don't know cubic inches so good...350?) in a very gently driven truck. It has NEVER! been above 3500rpm. If we used the same brand and viscosity of oil, would UOAs be of any use for comparative purposes regarding oil quality and longevity? I'm not sure that looking at only the UOA, and knowing nothing about the vehicle, driver, filters, previous oil used, location, time of year, etc. (again...so many variables!)...can give us a truly scientific picture of an oil's quality and performance in GENERAL. I think it may tell us what seems to work well for SPECIFIC engines; and certain drivers...but extrapolating that data to other engines,and drivers might prove to be questionable. Any comments...?