Necessity is the mother of invention.
That gif of that excavator sliding downhill on ice reminded me of a story a Catskinner once told me of a D8 he was operating to open up a skid road that was grown over by Douglas fir. The Cat ended up sliding down the road over the young fir, which were acting like slides. "Not even dropping the blade would stop it", he said. The cat continued to slide down the road over the fir it was barreling over, uncontrolled, and finally came to a stop only when it hit the bank of a turn. That was John Ciro's older brother, Rodney, who told me the story. He went on to say, "Jer, if that cat went over the edge, rather than hit the bank, it would've been curtains for sure"!
Who would have ever guessed such a thing could happen.