Look at the braking hand. If loaded, this rope will go through the belay device like there is no tomorrow. Without autolocking device (like Gri-Gri), the brake hand has to be in braking position. It's the angle of the rope, which is basically useless in the technique shown. IT IS DANGEROUS!
I guess you aren't into sarcasm?
Not into sarcasm? A six year old video making the fun of the way americans belay?!?!