frequently?

Often enough that I wouldn't take a chance with my health by trying this app.

I've also practiced martial arts for over 20 years. I know that while I can hold my own in a self-defense scenario, arranged fights are another story entirely. Even untrained people get in lucky shots, you make mistakes, you have a bad day... and there is no guarantee that your opponent will not have their own 20 years of training.

Or your opponent could be a psychotic jerk, and will just gouge your eyes out.

Fights with strangers is just a bad idea.

Honest question, would you rather fight a much larger person than you and could break your jaw with a single punch or someone who had 20 years of martial arts training?

Someone with 20 years of martial arts training. No question. Because the odds are that they also will know how to win a fight without permanently hurting you. You may end the day beaten and bruised, but probably not broken.

Check out this:

https://www.fbi.gov/about-us/cjis/ucr/crime-in-the-u.s/2011/...

Deaths per year (trending down is nice!):

    Weapons	        2007	2008	2009	2010	2011
    Personal weapons 1	869	875	817	769	728
    Other or not stated	1,005	999	904	872	853

Anyway, broken jaws and teeth are really expensive to fix. Like a bottomless depth of debt could result due to liability and personal injury. Even if you don't go to jail, it could be a life changing event in a bad way.

Uh, sort of, yes.

https://en.wikipedia.org/wiki/Rabbit_punch

http://www.fightingarts.com/forums/ubbthreads.php?ubb=showfl...

You'll probably want a degree of comraderie in a fight, otherwise you might be gambling with your larynx or maybe some other valuable vital organ.

Doesn't have to be that extreme in many cases it can be just a concussion which leads to intracranial swelling you feel "fine" till you go to bed and never wake up, other common side effects of getting repeatably punched in the face also include things like an increase likelihood of having a stroke due to blood cloths forming within cranial blood vessels (Circle of Willis, Cerebral and Lenticulostriate Arteries).

Killing a man with your fists isn't that hard, much training in various full contact martial arts actually goes into practicing how not to kill your opponent during a fight.