A few thoughts on that TX pile up. DFW area is full of elevated highways, with a maze of ramps etc. Sometimes if feels like miles of snarled highways all elevated. They do little if any salting, and rely on minimal sand use. Most times I swear they just wait for the sun to melt it which it does by 10;00am on many ice and snow days. This coming Sunday-Tuesday will be a mess there with temps near zero for a couple nights and several inches of snow coming. I've been there with snow and ice at levels I would say are just another winter day up here, but there everything closes. After driving in that weather there I realized it isn't the roads that are dangerous, its the drivers who know nothing about driving in it. The locals who do drive on those days drive at normal speeds, 75 - 80 mph on a sheet of ice, weaving around cars until they wreck. But the black ice that caused the massive pile up was not wide spread. Areas just minutes away had no ice, so I'm sure the traffic was flowing fast and heavy, unfortunately.