I view this as an interesting discussion, but I've come to learn that auto manufacturers have done a pretty good job at their OCI recommendations, with a few notable exceptions (GM) in the early days of IOLM. Most modern autos have IOLMs that take into account way more wear factors than we're talking about in this thread. While at first skeptical of IOLMs, I've come to rely on them, at least in in my Ram truck. My wife's Hyundai has an oil change "reminder" based solely on mileage--I'm OK with that also, as I get to set the mileage that it goes off, which is set with our driving habits in mind, as well as calendar days recommended by H/K. My Ram usually times out (one year) before the oil wears out, otherwise I'd run the IOLM down to the 10% range.
Good discussion, but my advice is, use the IOLM if you have one. . .if not, follow the engine manufacturer's recommendations and try not to over think it. . . but this is BITOG, I know. lol