Well I must admit my eyes started to roll as soon as I saw the title, but there are some interesting points in here...

I use Rotella as well, although my truck pounds it more than most of yours do, being a diesel. I use the synth in the truck, and the dino in my bike (KLR 650 - big single). I do want to send in a sample some day, to see if my interval is too long... I usually go about 7k miles between oil changes, since my filter is so expensive (and huge) but I wonder if that's too long...?

1991 HZJ77, 1999 KZJ90, 1999 UZJ100, 1992 M101CDN2
https://www.thegearheadproject.com/category/jdm-journeys/