I can't watch Youtube videos, but if I got the correct idea about what OP is talking about then there is no glitch. That grenade doesn't stop people from using super, it just kick your super energy bar backwards a little. I have had my lame moments when I have full super bar, I jump towards the group of opposing team players, get hit by that grenade and, instead of activating Fists of havoc, I bitch slap thin air and get shot in the head. That grenade is just fine - it depletes your super bar before you have activated it.