Custom PC Watercooling and Fan control system. Fan control help?

This is, in many ways, intended to be overly engineered just to ensure that my precious PC doesn't get damaged.

I've never seen a PC physically damaged from "normal" overheating. If something literally burns-up, it's normally damaged before you get smoke & black-dead components.

I haven't had a CPU overheat in a long time... When it did happen (due to a "frozen" CPU fan) the CPU would slow-down to a crawl to protect itself and there was no permanent damage. I believe Intel & AMD processors both have over-temperature protection built-in.