Fascinating. Really. You sound as close to a rocket scientist as we are likely to see on this forum.
I have always run premium and will continue to do so. My sense was essentially what you have stated - I wanted to protect the engine from unecessary wear and the marginal cost was insignificant.
Going back to the OP, if you have the car for 3 years and then turn it in, perhaps you just don't care. I wouldn't know, since I buy, hold and drive. I suppose those on a lease have their decision to make. But thanks for the thoughtful post.