I of course agree that when you are in a dominant position you can bite him as well even do him more harm, but when I'm fighting someone I don't want to bite him first, I'd never do that. What happens if he bites my neck and cause some serious damage? Jaws are incredibly strong... Wouldn't a strong bite on the neck finish the fight? Isn't it like killing technique? And how many people really think about protecting their necks when the fight starts? I don't know... I'm just confused. If the guy attacks the groin or eye gouge you, it is painful and uncomfortable, but it doesn't seem serious as neck biting, at least to me.