If he was doing a burnout, the back wheels didn't "break loose" when he backed off. More likely, he wasn't quite pointed straight and when he backed off the back wheels regained traction and pushed him in the direction his front wheels were pointed.
Anyway, I see lots of videos of people deliberately spinning their tires and they don't back off soon enough when it starts fishtailing and lose control. Worst is when they give it full throttle while they're still turning. What are they proving? That they don't know s%$*t.
:BangHead: