I tend to interpret the Xin Sheng movement as Sun Tzu cleverly identifying a sufficently general thread, a commonality of general identity for the ethnically and culturally diverse peoples of the Capellan Confederation. A "theme" that the populations of the Confederation's worlds could rally behind, and that could be legitimized through the CCAF's renewed prowess, initially demonstrated in the reclaimation of the worlds of the Chaos March. It was supposed to teach the people of a state that had historically been seen, and was indeed seen by its own people, as weaker than its neighbors, that the Confederation need not bend the knee to anyone. Put another way, it is one thing for a once weak person to become strong. It is yet another, to make that person proud.
Meh, my two cents, at any rate.