I can see this being useful in an emergency. I can also see a lot of people with lesser skills having unfortunate incidents resulting from stored energy!
Ingenious method. Seems like a lot of work though. The video was painfully slow, he could have explained it and demonstrated it in a third of the time ..... southern folk "aint in any hurry I rekon"
I tried it out years ago on a truck in my driveway. Truck wasn't stuck I was just testing. Had the ebrake on to see how much pull it had. Slow for sure but it pulled a 3/4 ton truck 24" in about 30 min start to stop.