The Chain 'threw' the window...

I wanted to get your opinions on the scene where Sam threw the chain through the window at the 'dozer driver: Would the guy have been really knocked unconscious like that? I mean, he threw the chain through a closed window (which possibly would've slowed it down), and the chain didn't even hit the guy in the head or upper body, but in the back & side... is that really enough to knock someone unconscious? Just curious.

: )