Oh man, that’s tough. First you get hit in the balls, then your head’s ripped off…
Please forgive me...but I'm curious...[Why isn't a knee to the groin a more common fighting tactic?]
I think this is the main reason. Unless you’re a kick-boxing expert.
Personally if I was ever in a situation that desperate that I needed to do a groin attack I’d just punch, or grab and crush.
I think it is fairly common to see this in female-male (or scrawny male vs behemoth male) fights, in real life, in self defense classes, and in fiction.
For male-male fights it usually only used where one of the parties is not fighting willingly, and even then usually as a measure of desperation.
In real life fights, the fighting is usually a dominance game, more about posturing than anything else. Or about being drunk, in which case strategy doesn’t really factor.
Martial arts classes are typically more about the art/sport and building confidence than in preparing for real life fights. And of course in official contests those sorts of things will be prohibited.
Martial arts movies too tend to be somewhat ‘honorable’ and ‘showmanship’ oriented so you won’t see that sort of thing unless it’s a Jackie Chan movie in which case the groin injury will be caused by some kind of seesaw action.
You might see this in Bruce Willis sorts of movies, where the stakes are high and the hero is an anti hero and he has to win by any means.
The main reason overall though, is that most fights, real or fictional, fall into a reverse bell curve, with non lethal at one end and lethal at the other end. Groin injuries would tend to fall in the rare in between sort of fight. At one end, most of the sorts of fights that will occur where neither party intends to kill the other will also not be the sort of fight where they would aim for groin. On the other end, the sorts of fights where either party wouldn’t abstain from groin injuries is also the sort where they wouldn’t bother because they have a weapon or other more efficient means of destruction. Groin injuries are for the rare fight which is unexpected and one sided, and is usually a desperate act. It’s also an awkward move - only useful with the right kind of set up and easily blocked by anyone with any sort of fighting skill.
Right. If I intend to kill the other guy, I’m not going to kick him in the nuts. I’m going to get a gun and shoot him in the face. And if I don’t have a gun, I’m going to run like hell rather than fight.
And if I don’t intend to kill the other guy, why am I even fighting this guy, anyway? If the point is to disable him to allow me to run away, my preferred method is to run away sooner. If the point is to show that I’m a tough guy, well, it turns out that I’m not so tough.
It’s hard for me to imagine getting into a shoving match with another guy unless it were a matter of life and death. If it isn’t a matter of life and death I wouldn’t hit a guy in the nuts. If it is a matter of life and death I’d run away as a first choice, and use a weapon as a second choice, and if I didn’t have a weapon I’d be screwed anyway. Not that I’d call the nuts off limits, as that I’d be too scared out of my mind to deliberately target anything.