This thread is for the discussion of the advanced TSD form O Sip Sa Bo. Most of the time this hyung is taught at forth dan and above. O Sip Sa Bo is related to the Japanese form Gojushiho, which is derived from the Okinawan form Useishi. There is a lot of difference in interpretation across the cultures leading to a difference in practice. What do you think about this form? Do you practice it regularly? What applications do you practice? Where does the TSD version of this form come from?