The Emperor's Above Sword surely has its flaws and limitations, but outsiders have no way of knowing the conditions under which the sword can lock onto its target.
Earlier, the divine patterns on Xiu Jieming were activated, and the Emperor's Above Sword wasn't able to lock onto him, so it wasn't effective.
At this moment, more than half of the divine patterns on Xiu Jieming have dimmed, and the effect of the Secret Law is about to completely vanish. The Emperor's Above Sword has already locked onto him, and no matter where he is, Qi Tianxin can strike him, ignoring any defenses.
It seems that the Emperor's Above Sword is extremely effective in restraining Xiu Jieming, with its ability to ignore defenses, not even the Third Rank's Return to the True Self could block it.
Return to the True Self likely isn't entirely useless because if it were anyone else being struck now instead of Xiu Jieming, they would have been cleaved in two by a single stroke.
