"Slippery roads" are hydroplaning. Otherwise, you need to provide some alternative explanation for why gravity ceases to function, and allows a tire to lose contact with the surface.

You are apparently a few decades out of date with your understanding of the interface between rubber tires and road surfaces. It was once thought that rubber somehow "gripped" pavement, and provided the traction we all rely on. The advent of superior inspection tools, like electron microscopes and others, has improved our knowledge in this field, and we now understand that rubber tires provide traction by deforming into microscopic imperfections in the surface. And that gravity provides the force required to cause that deformation. This is why dynamic weight distribution, and the control thereof, is so critical to performance on both two and four wheels.

So, what you call a "slippery road" is, in reality, we now realize, just the hydroplaning effect of a potentially microscopic layer of water preventing the rubber from deforming into those imperfections.

This is obvious, in hindsight, because there is no other mechanism by which gravity could be disabled, in order to allow a tire's rubber to stop interlocking with the road surface.

The same effect occurs without water, when a tire is pushed beyond its limit, and it begins to melt. A thin layer of liquid rubber results, and behaves just as water does -- suspending the tire off the surface, and preventing tractive force from developing. This is how you leave skid marks on your fixie, or do a burn out in your Challenger.

I recommend that you (general) stop spreading obsolete and inaccurate information on this forum.