Actually some of the more sensible companies, that have vehicle fleets driven by company drivers, send the drivers to "Skid School " where they learn how to avoid and or deal with skids on snow covered or icy road winter roads. When I worked for Metropolitan Toronto Ambulance, all of us had to go through the skid school every two years, to refresh our driving skills.
The training school was on a decommissioned air force base, and we used the runways to train on. The runways would be watered and then sprayed with liquid soap, to simulate ice or snow conditions. We were driving our normal Dodge van Ambulance vehicles with a full load of equipment inside. The instructors would lay out a pylon course that we had to drive through at a specified speed, and each time though the curved course we had to drive at a higher speed to simulate a high speed run in city traffic. We also had to reverse through the pylons without touching any of them, but at a lower speed, of course.
One of the harder tasks was the "pick a lane " situation, where you would drive at a steady 40 mph speed, then the on board instructor would call out "go left" and you would have to make a fast lane change, to the left, which would cause the vehicle to skid hard. Now you had to not only control the skid, but stay within the lane markings, too .
Braking during a skid is not the right thing to do, as locked up front tires cannot effectively steer the vehicle. Steer into the direction of the skid, and keep off the brakes until you have control of the direction of the vehicle, and reduce vehicle speed by getting off the gas pedal. If the vehicle has an automatic transmission, put it into neutral, to cut power to the drive wheels. LOOK where you want the vehicle to go, and steer in that direction.
Like any physical skill, driving requires practice and education and repeating the process. JIM.