I don't you're getting Dave's point.
Factory thermostats were designed to run within the optimal temperature range of the engine. If you want to 'push' said engine past what you deem normal operation and create more heat, this isn't a problem for the thermostat, it's a problem for the radiator.
Think about in terms of a thermostat is a heat pump. You want your room at a comfortable 20°. What's going to get there quicker more effectively? The heat pump in the big lounge room or the one in the closet!?