More for peace of mind, but I treat every tank. Before my LMM, I had a 2015 LML for a few weeks. The CP4 thing scared me enough to think I should treat every tank. We also don't have commercially available bio in my area. I use the approx recommended concentration on the back of the bottle. It usually equates to I pour about half a bottle of stanadyne in per tank.
I started with stanadyne performance deposit formula, then 4 weeks of regular performance. No issues, no idea if it ran better cuz I did that from tank #1. Currently still using stanadyne each tank
Switched to opti-lube when I read the spicer report. I didn't notice any improvement, but my wallet was lighter so I couldn't see why paying more is better for the same-ish product
When I can't find stanadyne, I will use PS gray bottle. The truck runs fine, but noticeably rougher and more exhaust smell at idle.
All that is subjective...