I don't see the point of showing Karatekas doing regular Karate moves and saying that its groundfighting in the since that we are stating, of course there has always been kneeling finishing techniques and counters to them grappling. But not hold down or rolling techniques as in Wrestling, Pankration, BJJ/Judo, Sambo or Jujitsu. I've studied Judo and some of the others Japanese arts and know the difference. At one point your rarely saw Jujitsu using many hold down or submitting from the ground techniques they would go in for the maiming technique as did Karate.

Theres no debate it exist but not in the Kata system past on in Karate. I never even heard that it was implied as stated above JJ rarely used hold down submisson unless they were taken prisioners otherwise like Karate they took no prisioners.