said by mattmag: when the the Thermostat fails, it normally fails in open position. said by Mospaw:
It's misleading to imply that this coolant will somehow prevent an engine / cooling system with issues form overheating, though.
A too-hot engine causes damage, no matter what temp the coolant is. The fact that the actual coolant hasn't "boiled" is truly immaterial. The metal components are what matters.