I’m guessing you’d feel the drag towing an helium filled, exercise ball sized balloon while ripping pow turns but the principle makes sense and it was the available technology back in the day. I’m thinking the tether should have been about 4x longer. It might seem like a cartoon version of avalanche safety but without the benefit of modern day beacons and airbag backpacks this was apparently the best option in 1974. Pretty sure they had winter hats back in the 70’s as well but don’t tell that to the dude in the yellow ski sweater….rightous flow on that dude.
Related: Using Balloons For Avalanche Safety