Throughout his entire competitive career, Oates was tweaking, improving and adding different elements to his Sumi gaeshi.
There were three important reasons he used Sumi gaeshi -
Firstly, to score. Secondly, to get an attack in - this, he said, was a key tactic. With his opponent under pressure and worried about a penalty, they were forced to open up, which would create more opportunities in Tachi waza. Thirdly, he used it as his primary weapon for entry into Newaza. Against a few players, Oates felt that he had little chance of scoring on them when standing up, but felt stronger than them on the ground.
Across these videos Oates reveals his Sumi gaeshi.