I posted a reply on streetfire.net already about this vid.
Basically I believe the dynamics at work in this vid to be BS. If you notice the first car, it is simply revving the engine. If it were attempting to engage clutch and move forward, there would be SOME bit of forward movement shown in his arms. There is none.
The second car is doing a burnout. If he wanted to (because he is a pretty strong guy) he probably could have pulled it backwards a bit. How many videos have you seen where someone is doing a burnout and some knuckleheads are pushing the car side to side? Now when the tires HOOK UP it becomes a completely different story and he is forced to let go or lose his arms.
Let's see him try it with my Z!!