Static friction vice dynamic friction

Corky Scott wrote:
I never had the money for such a course, but when I was a fresh faced
driver, I took the family wagon out one night during a slippery
snowstorm and practiced skids and skid recovery. It was instructive
to learn that when you stomp on the brakes and lock up the wheels,
steering input quits working. I would center myself on the road and
stomp on the brakes, then I discovered that I could (and did) spin the
steering wheel from lock to opposite lock with no change in direction
of the car. But if I lifted off the brakes while the wheel was locked
to one side, the car would instantly regain steering and lurch towards
the curb. Very instructive.
I was in no danger of hitting anything because I did not do this with
cars around and the streets were pretty wide and I did not need to go
very fast to skid. The lessons I learned that night have stayed with
me for 43 years. A locked up tire has no traction, nor can it be
steered. That's why ABS works, it prevents total lockup.
It was very smart of you to treat them to the Skip Barber course.