No why would he

What is the relevancy of his performance with the data you sought here🙄❓

اللعب كريكيت واحترفها واهتم في امورك ولا تتدخل في شي لا تعرف عنه شي.

حياك الله سيفو تركي 🌹

Were you taught under Nagata Sensei? I just got back into it, and my Sensei's Sensei (edit: my Sensei's Sensei's Sensei) is Nagata Sensei. When I first was doing it, about 30 years ago, I was learning under Ross Sensei (who has sense passed), and his sensei was Nagata Sensei.

Not the way i learned it either

If sill interested in an answer, we do it the same way, but bunkai often varies from the person teaching you to teaching you. To me it is a throwing movement - I have seen moves like this in Judo and the application works really good. When in kokutsu/nekoashi dachi you hold your opponent with the hikite hand in shuto and the other one performes like a downward nagashi uke style move it could mean like holding one hand on the body of the opponent and the other is grabbing e.g. the arm while pushing down. The stiff leg is lifted to throw the opponent (so your hips touch in the application). If the opponent does not fall down, move to kake dachi and lift the opponents arm up (nagashi style hand to body, hikite hand upward, face to upper hand) to break posture. If still no fall, continue in shiko/kiba dachi (varies from style to style) and perform lower gedan barai with shuto, this is always a throw in our style - you push your knee into the knee from the opponent and "gedan-barai" his upper body down. But again, this is just one form of bunkai application that makes sense to me. I am neither sure or in the position to claim it to be the "only right" application. Would like to know different applications, too! Karate is family, not hate.

It's not a back kick. It is a "drunken movement", I.e.exaggerating going with the pull of an opponent, then stomping the rear foot down on their knee/leg. Thus, making speed and power to a stomp, meanwhile allowing them to present the target. That's the old application. Applications in kata are much closer than in competitive sparring, essentially grab/punch range all the time. Including kicks.

Keep in mind this video is very old, probably (not sure) from the 70's. Ippon Kumite excersises have been slightly modified ever since, but this is still a great reference. I am a Seikbukan student too. These are the japanese names I was taught by my sensei: 1. Nagashi Uke + Chudan Tsuki (00:04) 2. Jodan Uke + Chudan Tsuki (00:18) 3. Ryote Uchi Uke + Uraken (00:33) 4. Uchi Uke + Hiji Uchi (00:48) 5. Yokogeri (sometimes this is performed witha preceeding Shuto Uke or Nagashi Uke, not in this video though). (01:00) 6. Mawashigeri (sometimes this is performed witha preceeding Shuto Uke or Nagashi Uke, not in this video though). (01:16) 7. Ryote Soto Uke + Chudan Tsuki. (01:27) 8. Juji Osae Uke + Uraken. (01:38) 9. Juji Uke + Tekubi Gatame. (01:51) 10. Kake Uke + Maegeri. (Today this exercise adds a Jodan Hiji Uchi). (02:10) 11. Juji Uke + Ude Gatame. (02:20) 12. Shuto Uke + Shuto Uchi. (02:39) 13. Juji Uke + Hizageri. (02:51) 14. Shuto Uke + Osae Uke + Uraken. (03:00) 15. Ryote Kake Uke + Ude Gatame. (03:15) There are several others not in this video, like I said, this is a great reference but it was long ago.