I had to go find it on youtube. Yup, that's a Blazer alright.
I wonder what the whole story is there. Even if brakes were lost, if it was in low range and held in 1st, (Even with an automatic) it might've been a scary ride, but not a 60 MPH crash over the edge. Did a drive line break? But then again, the transfer case should be locked front and rear in low range, so she'd still have an axle on one end or the other for speed control. Did they start down the slope in high range and just lose it?
I can see if you're not ALREADY in a low gear on the steep stuff, you might lose it. That's why I like the stay-in-what-was-selected-last feature. Makes me think of Imogene Pass, the Cork Screw, etc. in Colorado. You head down in 3rd or 4th, and it's already a goner. It will take off so fast, a downshift (if it even happened) would cause a skid on a road that's only 1.1 Jeep widths wide in the first place.