Uhm, what can I say.... in a fight I use my common sense first.... and this is the best way to protect yourself.
Violence should b the last thing you should do......
I do practice Ninjutsu, and its a mix of many Ryu's if I can say that..... Bujinkan Ninjutsu is what I am currently studying though.....
IMHO in a fight you should first of all not fear your opponent, but also do not underhestimate him. In order to win you must be able to use the things that surround you. to be intelligent and creative.
For example, my skill with swords does not need to be used with a sword, if there are sticks around me, even if thin and seem useless, i use em.
They still may be useful on certain body parts.
Though, I always try not to really hurt my opponent as much as possible, not like the fall on the knees thing and knee him on his face *coughdarkmagiciancough*
The essence of Ninjutsu is to survive, and a Ninja does not necessarily have to kill someone in order to survive...
Violence is bad, and weak people sometimes are the first one to use it. when you have confidence in your strenghts then you will know that violence is not what makes a person strong.
Remember, A good soldier is not violent. A good fighter is not angry. A good winner is not vengeful.
Ninja seishintowa, shin shin shikiwo shinobu. Ninnikuseishinwo, konpontosuru. Chijokuwo shinonde, Uramiwo Houjisuru.....