Ring vs. Reality

The issue of whether or not a particular martial art is effective or not comes up all the time. What is realistic?

1. Actual hand to hand combat in war.

2. Surprise attacks,
-muggings
-kidnappings.

3. Fights for honor
-the school yard
-the bar
-arguments (petty and otherwise)

4. Crazy people, drunk or on drugs.

5. Intervening on behalf of someone being bullied or mugged

6. Intimidation (including turf defense and "hating out")
-by an individual
-by a group.

7. Professional encounters
bouncers
body guards
police.

A matched fight has several things these above fights don't. The first is parameters. The fight happens right here, when they ring the bell. And there are rules, no weapons, certain blows likely to maim or kill are usually forbidden. The fight will be stopped if one person concedes defeat. In addition the only surprises are likely to be techniques or strategies. The opponents are roughly the same size and wear the same types of gear. There is likely some advantage gained by conditioning or numbing one's body to take a hit (of little use in a knife fight for instance.)
If you are training for a matched fight you train specifically for the constraints of that fight, even down to studying the previous fights of your competitor.
Matched fighting and real fighting are completely different animals.