Scott Shaw was Master Yoon's Senior Black Belt and his first Certified Master Instructor in the U.S. 

Grandmaster Yoon was one of Hwang Kee's original students. Hwang Kee was the founder of Tang Soo Do Moo Duk Kwan. He was also one of the original masters to leave the parent organization and help in founding the Moo Duk Kwan branch of Taekwondo.