I've been thinking about this for a while.
Could a magnet be used to effect the thermostat without potential major problems?
Not totally control it, but influence it and change the operating temperature.
Kind of be a 2nd force in addition to the spring.

My idea was, that it would be nice to push a button, maybe a 1/2 mile from home, and dump a bunch of heat out of the engine before getting parked, to reduce heat soak after shutting down.
When driving, it makes sense that the incoming air would keep everything relatively cool, but after shutting off, the heat just builds up until it cools off.
I know this wouldn't effect the heat from the turbo and exhaust, but there should still be less heat total with less coming from the block, right?

Plus, say the magnet causes the thromostat to operate as a 120* thermostat, I could activate it a little ways from home, then actually turn it off a 1/2 mile from home, and then all the air coming through the rad should be cold, cooling off everything else?

 

I don't think that would help much. On one truck I had an electric fan run straight off the battery through a temp controller, and had it set to kick on as soon as the thermostat opened. It would kick on a couple times after shutdown since there is still some coolant circulation by convection. Scared my ex a few times, walking past the front of the truck and suddenly a nice big fan kicked on-

 

Sure, but how would that get much heat out?
You still had a normal thermostat right?
I'm talking about "influencing" the thermostat to dump heat close to the driveway.