My "Hole in the Wall" house is a very special place for me. Thanks for the complement. By road, my closest neighbor is a mile away. My closest neighbor by air (1/4 mi) takes 40 minutes to hike to and 45 minutes to drive to. :wink:
The traction control in the Tesla Model S is amazing, perhaps the best in the world. With good snow tires, it challenges a good AWD car. As long as the snow is plowed and less deep than the bottom of the car, it does very well.
As I understand it, the traction control in the MS is (although perhaps the world best) of a conventional design. An open, simple differential creates equal torque at each wheel, but allows the wheels to turn at different speeds so the car can go around turns without scrubbing rubber on the pavement. Equal torque works great as long as each wheel has traction. The problem is when one wheel starts slipping. A slipping wheel has zero torque. Because the open differential is an equal torque device, the slipping wheel transfers zero torque to the wheel that has some traction. In very simple terms, what "real" traction control does is to apply the brake on the slipping wheel. The torque created by this braking action reflects torque through the differential to the wheel with traction. The MS has a low moment of inertia electric motor relative to a large ICE. With this and many fine details the MS has a wonderfully capable traction control.
However, nothing in this will turn a wheel backwards. I think that your salesman has heard, or is creating, a huge hyperbole with wheels turning backwards.
My other vehicle here in Pagosa is a 2000 Jeep Cherokee. It has a very conventional 4wd. I can lock the transfer case so that the front and rear axels turn at the same speed. This is bad on dry pavement, but fine if the things are a little slippery. Next, I have aftermarket air-lockers,
Air Lockers
These allow me to selectively switch the axels from open differentials to solid (no differential) axels. When I lock up the transfer case and lock both differentials, all wheels turn at the same speed; if one of four wheels has traction, the jeep moves forward, bulldozer mode. Yesterday, I drove the Jeep and the Model S up my driveway; later I walked my lab down and up the driveway and looked at the tracks. Its pretty easy to tell the tracks apart, very different tread widths and different track widths. The MS climb tracks were chattered blurs as a result of a very busy traction control. The traction control did well, but the tires were always working the snow. The Jeep tracks were clean and distinct; the tire tread was clear and distinct. The locked axels of the Jeep just rolled up the hill.
The MS will push through 5-6 inches of powder up a 15% grade and the Jeep will push 30-40 inches of powder up the 15% grade. The Jeep is a great tractor, and the MS is a wonderful luxury sedan. :biggrin: I love both in its home environment.