Groin Kicks?

My first style of martial arts I ever studied got a lot of things right in the 1980's that I have only come to appreciate in the 2020's. The style was most often called "Tae Sho Arnis," though it was also called at other times "Tae Sho Karate Do" and "Combat Arnis." In an era of Kumite Point fighting that was decaying the quality of martial arts in the USA at the time, Dave Bird decided to combine the best aspects of the martial arts he had mastered: forms from Shotokan Karate, free sparring from old-school Tae Kwon Do, and Arnis for weapons technique. Though he his style produced kickboxers who competed in our area, most of the sparring in class was continuous controlled contact and included both unarmed sparring and stick sparring (though we did also train for Kumite Point Fighting tournaments a few times per year.) 

In the 1990's this controlled contact free sparring would be lost in the USA as MMA got more popular and we over compensated for our participation in no-contact kumite point fighting, but would return to the MMA community by way of Muay Thai within a few decades. But there's something that has not returned 1980's controlled contact free sparring that we used to spar with frequently: groin kicks. I am not sure if these came from Shotokan or TKD, and I have wondered if they came from Arnis; see the kick at 1 minute 26 seconds in the last video I know of featuring Dave Bird:

Later as I studied Chinese martial arts I noticed that the most basic kick WAS the groin kick. If you pick your knee up with a groin kick so that you can stomp forward with the bottom of your foot you get a front kick. If you swing your groin kick around to connect with the side of your target's body you get a round kick. Watch all of this UFC champ and Shotokan master's kicks carefully and you will see many of his kicks that connect are not much more complex than a groin kick (especially his round kicks that connect to the body):

This Kung Fu teacher does a great job of explaining how in traditional martial arts, many different kicks are built from a basic groin kick:

To this day when I am free sparring with kicks I have to be careful because my feet target the groin like a heat-seeking missile because of all that free sparring with groin kicks I did in Tae Sho Arnis. Our basic strategy was simple enough: groin kick to set up straight punches to the face, and straight punches to the face to set up groin kicks. To block the groin kick we would bring up a knee. To counter the knee block we would use a round kick to the calf muscle on the blocking leg. To prevent groin kicks we would try to step on their lead foot as we threw straight punches. In retrospect there was a lot to like about that strategy from a self defense perspective. 

When going full contact you can't count on a cup to protect your groin. But now that controlled contact free sparring is back to the USA, groin kicks are still not used in free sparring because most people doing free sparring are training for combat sports were groin kicks can get you disqualified. But this raises the question: should students who train for self-defense-only include groin kicks in their controlled contact free sparring?