How much conscious control did Deun Yu have over his Bak Ming Sun Gung absorption power? Most of the time, it only seems to switch on when he's defending himself or his friends against enemies, but sometimes, it seems to just switch on spontaneously (like that time at Man Sau Manor when it just seemed to switch on for no reason and he absorbed the inner power of Chung Man Sau, Jin Bo Bo, Chung Ling, Wan Tsung Hok, and Divine Crocodile).