Sometimes you cant help going to the ground. You could slip, fall, or get sucker punched without ever seeing it. There are so many factors involved in personal protection and self-defence. One may not want to go to the ground, but once your there you have to know what to do. In self-defence, you tactics should be based on getting back to your feet, but you may have to grapple before that can happen.
Learning how to maintain positional control standing up or on the ground, is important in any type of martial arts program. Biting may be a last resort, as there are many communicable diseases like Aids and Hep A, B, and C out there. Eye gouging or groin and knee strikes can also be very effective on the ground. Dont forget, just because your down does not mean you have to grapple. Combining Eye gouging, groin strikes, knees and elbow with grappling can help a person to get back on their feet to a solid platform. When your on your feet you have a better chance of stun and run tactics.
if a weapon is draw, get it out of the person's hand and cut his guts out. if someone else dicides to help out, on my side, push 'em out (i can handle myself thank you). if someone else decides to help out on my opponents side break idiot numbers arm, elbow, knee, or what ever limb presents it self to me and start playing with idiot number 2. ohh and why cut his guts out? well he did once, he might do it again. and break a limb? so i d on't have to deal with idiot numbers 1 & 2 at the same time for as long. and pinching does do much other then make your fight look like porn. if i use an eye gouge, that wont heal, an brocken limb will how ever. if i bite and they aids, well i was absinint for nothing, lol.
Remember when biting to go for soft tissue such as ears, noses, muscles but always bite with the back teeth. Clamping down with your front teeth is a great way to earn that hockey player smile when your opponent jerks away from you.
When head butting, always use the crown of your skull. You may win the fight but still lose the war if you knock your opponent out at the cost of giving yourself a concusion.
One word. SURVIVE. If survival means a bite, tear, rip, pull, gouge then yes do it. The "ethics of combat" only stand if you're still alive after combat and most "combat ethics" were created by people with either (a) little experience in combat or (b) traumatic experiences involving combat and wanting to make the world a better/nicer place. Since the world still isn't a nice place, survive by any means necessary.
Nothing wrong with biting, eye gouging, hair pulling, pulling eyes out and earlobes off....
...Providing you have some REAL ability (and by that I mean, you have empirical evidence garnered through experience against resisting opponents), that you can back all that up with. Those things are not substitues for the actual ability to fight, that is developed through a more standard functional and performance based art-form(s).
If you're good at boxing, those tactics will work. If you're good at wrestling in the clinch, they will work. If you're good at Brazilian jiu-jitsu (etc), they will work. If you CAN'T fight in any of those ranges there is NO reason to think that you can make any of those techniques work. That is why I don't believe in the Kino Mutai stuff. How DO you practice that art anyway?!
Its like Jerry Wetzel says regarding knife fighting (and I'm paraphrasing), if you can't fight WITHOUT a knife, don't bet your life on your ability to fight WITH one.
The same could be said regarding these "foul" tactics don't you think? I certainly do.