Let me just say this... MMA is the new "Bruce Lee". They are no more dangerous than anyone else. What you see in the MMA / UFC matches are just another RULE BASED martial art put in an arena where it is allowed to shine. The point is, in the MMA matches, there are rules. First take a look at the ring, it is padded and the fighters are wearing pads on the fists, wrists. Second, you are not allowed to grab “the cage”, gouge eyes, rabbit punch (punch to back of head), et cetera.
In a “real fight”, there are no rules. We have all heard this 10,000 times and that is the point. If someone tries to grapple, or rushes you GRAB THEIR EAR AND RIP IT OFF, GOUGE THEIR EYES, PUNCH IN THE BACK OF THE HEAD, et cetera.
When you watch MMA, you are basically watching a SHOWCASE for that fighting. Yin and Yang buddy. EVERYTHING has strengths and weaknesses and is constantly moving from a position of strength to a position of weakness all the time. Study human anatomy, practice punching those vulnerable areas. Practice drawing and getting your knife and gun into action with each hand. REMEMBER, PRACTICE, THINK about what you would do and when you would do it. Do this all the time and you have a HOPE of stopping a violent encounter. It doesn’t matter if he is an MMA star or a thug, the action happens so fast, if you are not conscious of the weapons you have and how to react, you will not make it out, hell read the thread Jeff White put up on guns being "magic". There are loads of times when Gunfighters, dangerous men in their own right, got killed. Read how John King Fisher and Ben Thompson, both very well known and very dangerous gunmen, got killed. Basically, someone distracted them and then two people ran up and stuck a gun both John's ear and Ben's ear and pulled the trigger.
Mad Eye Moody from Harry Potter says "CONSTANT VIGILANCE!!" I couldn't have said it better myself.