Why is it dangerous to operate a hydraulic retarder or engine compression brake at maximum stage on wet, icy, or snow-covered mountain roads?

1. High retarding torque applied exclusively to the drive axle can cause the drive wheels to break traction and lock/slide, triggering a tractor-trailer jackknife
2. The retarder will overheat the engine cooling fluid within seconds in sub-zero weather
3. The hydraulic oil will instantly freeze in the retarder valve block and burst the radiator
4. The auxiliary brake will deactivate the pneumatic trailer supply line and dump trailer air