The time I took a Dirty Boxing Seminar with Randy Couture at the RevGear conference was very helpful in making my High School Wrestling experience relevant to MMA and Combat. It was like a light bulb went on, like I had these skills but hadn't fully integrated them. I had never fully connected HS Wrestling to my Martial Arts training. It was less "Dirty Boxing" though and more Dirty Wrestling, getting to a wrestling tie up and striking. Now holistically I blend all the things I learned into one cohesive fighting system, whether it be stand up fighting, grappling, multiple opponents or weapons there are universal fundamental basics that apply cross-sectionally and make it all flow.
According to Eddie Bravo, Bruce Lee said "A guy who’s been wrestling and boxing for a year can beat a martial artist who’s been training for 15 years."
In general I believe this to be true especially if you look at the state of Martial Arts in the 60's and 70's while Bruce Lee was alive. Some traditional martial arts, this definitely still applies.
I've heard statistics than many Black Belts in traditional martial arts lose their first fight, due to no actual fight experience and practicing martial arts that don't pressure test.
I've been doing martial arts for over 30+ years. Since 1992.
In High School in the early 90's I got my black belt in Taekwondo. I wrestled in High School I also trained in Eskrima, Kendo and Aikido during that time. I lost interest in freestyle wrestling because pinning a guy to his back didn't make sense in a street fight. At the time I preferred to punch and kick but then when I saw the UFC I wanted to get more into Submission Grappling/BJJ. So I started training in Trapfighting (JKD, Shoot Wrestling = Catch Wrestling and Muay Thai), Muay Thai, BJJ and Wadu Ryu JuJitsu / Kempo with Grand Master Pat Burleson.
Since High School I've trained Gracie Jiu-Jitsu, Gracie Combatives, BJJ, Krav Maga, Kali, Silat, KunTao and JKD. I'm a Black Belt in Combat JuJitsu / Shorinji Ryu JuJitsu, TKD and KunTao among other Arts. I'm a black belt or instructor in a few different martial arts.