What they need to figure out is the force that's required to cause someone to flip out of the track if they foolishly try to slow down their descent by applying unequal force to the sides.
But but but there's no TV outside! My in-laws amused me when they bought a cabin in the woods, then proceeded to deck it out with the latest flat screen TV and other modern amenities.
Not for long, probably!
My favorite answer: "Its mother screwed a peach" - Hire that man forthwith!