That next year I met him, I was a yellow belt, at the Sunnyside Garden “Tournament for a Master” in 1975, it would be our only meeting. I remembered that article and asked him about the Isshinryu Obi-Waza, but he said he didn’t remember the article.
There are four techniques in kata that could be obi-waza.
1. The first is in the beginning section of Seiunchin, where, after blocking a punch with a kakie-uke, the defender grabs his attacker and pulls him into an inverted nukite.
2. In the very beginning of Chinto, after the jodan juji-uke, the defender deflects the overhead attack to the side, then thrusts into the attacker's midsection with a right inverted nukite, then grabs the obi (or maybe the floating ribs) and strikes with a left back-fist or hammer-fist.
3. In Kusanku, after the flying crescent kick, kneeling avoidances and chudan-uke, two punches combination, one turns, performs a left open-hand sweeping block downward, thrusts underneath it with a right inverted nukite, grabs the obi and spins.
4. In Sunsu, after the elbow combinations, one turns, performs a left open-hand sweeping block--this time horizontally--followed by an inverted nukite, grab, and a 360-degree spin to throw the opponent to the ground.
Certainly reasonable suggestions.
More research and study is called for.