Why do you think a UOA is going to tell you which oil is "better"? Seriously?
Wow, both a red herring and an ad absurdum
tucked neatly together in one line. . .
First, exactly where did I say that a UOA will tell you whether or not one oil or another is "better"? I didn't.
reviewing my earlier post, I can see that I myself was vague. What I meant was that the 40 performed
no better than the 20; I was NOT alleging that one oil was "better" than the other. My apologies for the confusion. . .
Second, you are completely ignoring the context. The assumption amongst many members posting in this thread, and others like it, is that "thinner" oils are incapable of offering the same level of lubrication effectiveness as are "thicker" oils. UOA, at least the way we amateurs here use them, are not conclusive, but may
offer clues as to possible issues with engine, oil, operating conditions, etc. (or of course, combinations of factors). Though the cited UOA is not, repeat not, conclusive, it is still pretty interesting to see a pair of UOA in which the 20 wt appears to have done just as well as a 40, in the context
of multiple arguments that this can't be so.
Now, what a UOA might
show you is where one oil or another is more effective than another in certain measurable parameters. Note that neither here, nor anywhere else, do I use the hopelessly vague term, "better".
In conclusion, let me turn it back to you, BGN, and rest of the thick worshipers: is it not interesting that there is virtually zero difference in the wear in this engine whether it's using a 20 wt oil or a 40? Yes, it's just one car, and yes, it's just amateur UOA, but still, those numbers are very steady.