When Wong Yung was injured by Kau Cheen Yan's Iron Palm, Gwok Jing was unable to heal her injury with the 9 Yum Jen Ging. Wong Yung explained that 9 Yum could do nothing about Iron Palm injuries because 9 Yum energy is yin while Iron Palm energy is yang. Therefore, they needed to visit South Emperor 1 Deng so that his yang-based 1 Yeung Finger Technique could heal Wong Yung.
During HSDS, however, when Cheung Mo Gei was injured by the very yin Yeun Ming Divine Palms, only the extremely yang 9 Yeung Jen Ging energy was able to fully heal him. Doesn't that contradict what was described in LOCH?