Honestly, I don't think I would eliminate the T stat all together, but maybe put a 165 degree in with a 1/8 bleed hole to get to temp quicker and let the pump modulate from 185-190 degrees, then from 190-200 modulate the fan. Then you maye need some sort of PID control system with all of these interdependent loops and latencies to keep it from oscillating wildly. That's part of the reason I have the fan bang bang, on or off with a 5 degree hysteresis.
Hmmm...all the recommendations I've seen for EWP use is to eliminate the Tstat and use a sensor based EWP controller. Certainly that's the recommendation from Davies Craig in their installation instructions.
Does anyone know if the OEM cars that use an EWP do so without a Tstat? For example, do the BMWs that use the Pierburg EWP do it solely with electronic controller or do they also have some sort of physical Tstat?