180 or 190 thermostat?

Fine, you're the chemist/physicist, I'm just the dumb Engineer with nearly 40 years of messing with engines who took the watered down thermo class more than a decade ago because I didn't need the full blown class.

C is a constant for any particular material or combination of materials. I didn't feel the need to muddy the waters with mentioning that. Most eyes glaze over as soon as the math goes past simple Algebra. You're taking this way too literal and in-depth.

The t-stat can't produce the pressure, it is a resistor. Something else produced the localized increase in pressure. Wait for it, the only thing that it could be is the pump!
So if there is a localized increase in pressure then it MUST be in the conductor between the pump and the restriction. That pressure will be uniform in that whole section of the conduit. Which just happens to be the coolant passages in the block. (Note: I'm intentionally leaving out other stuff that is there, but conceptually doesn't matter and only serves to muddy the waters more.)

I really don't care if you're too immersed in your own ideas to even consider that I might have a point. Mislead folks with your blindness to the fact that in spite of your education you may not actually fully understand the whole system. It is clear to me from some of your statements that you don't. I won't claim that I do, that's why I've been calling it a theory, not a Law.
I'm done here.