content: From her? At that angle? Not as much. With a headbutt you actually want to be striking down with the crown of your head onto the bridge of their nose. Otherwise you're not able to generate enough force to do much except cause pain in both participants. A punch is much more energy efficient. What I don't understand is how they could get to the point of coming up from below to break the grip and going straight for an eye-gouge instead of just punching them in the face repeatedly from the same position inside their guard... or starting the whole thing off with a kick to the flesh purse.