I believe that was more of a tongue in cheek comment on the history of TKD. TKD used to be pretty much Shotokan when it first started as a style. It used the same forms as Shotokan. Some Korean styles, kept that like TSD/MDK. TKD evolved/changed further to remove the Japanese roots and try to make it more culturally "Korean" in nature. Part of this was removing the Japanese kata and creating their own forms. So, his point was that if you are doing all of the Shotokan forms, then it wouldn't be TKD. TSD even though it uses the Japanese forms, invented a new history about the forms and claimed that they are Chinese in origin and learned there. I could be completely wrong, but that is how I took the comment.