Just pulled this from Ford workshop manual.
Thermostat
The 1.6L Duratec-16V Ti-VCT engine is equipped with an electronic thermostat. The electronic thermostat will manually open if the coolant temperature has reached 98°C and there is no current flowing to the thermostat electrical element. When the engine is under load the electrical thermostat will receive a current from the PCM. The electrical current will heat the element inside the thermostat to allow the engine coolant to flow through the radiator when the coolant temperature has reached 60°C.
Coolant degas shutoff valve
The coolant degas shutoff valve is designed to stop the degas process during cold start. Shortly after the engine is started, the coolant degas shutoff valve will close and reduce the coolant flowing through the engine which will improve cold start fuel economy and warm up time of the coolant. When the coolant temperature has reached 80°C the valve will open and allow hot coolant to circulate through the coolant expansion tank.
Assuming it applies to versions used by MMC, it goes some way to explaining unexpected coolant temps especially with non-standard installations.
