Physics of Winter on Cars (a Lesson in Thermodynamics), or Do I know WTF I'm Talking About?

Heat flows from an area of high thermal energy to an area of lower thermal energy until thermal equilibrium is reached.

Driving during the subzero winters in Minnesota, I think that driving at high RPMs in the 70-80 MPH range would be detrimental to one's engine, at least more so than driving at lower RPMs, considering that rapid cooling of a hot metal can warp the metal. Also, since heat transfers faster when the thermal energies of two different matters in contact are further apart from equilibrium. Perhaps not, though, since the cycle of an internal combustion engine constantly supplies thermal energy to the metals and the oil. Does anyone reading this know if this process is very bad for the engine? The internal combustion engine process has got to be at least minimally damaging to the entire system with the physics involved in the entire system, otherwise, we wouldn't ever need to buy new cars. I guess this has less to do with cold weather and cars than it does with just the normal wear and tear of a car's engine.

This How Stuff Works article has a few good tips on getting better fuel economy and something about warming up your car.