do NOT assume biting someones tongue off will immobilize everyone.
it worked on this guy..
but pain and peoples responses to it are so variable...add in what ever drug cocktail if any the attacker is on...(if cocaine and its been snorted the odds are very high that area of the body is already anesthetized, even rock would have a numbing affect tot hat area).
its not as save a bet as it appears
another very real possibility is when you bite someones tongue off the attacker only gets more enraged and will seriously harm you more...
if not kill you
if you want to get away. you need to go for the vitals...
in my opinion
this girl did what she had to and also is lucky the guy didn't after the fact slice and dice her..