The method of renaming for longevity was not a legacy that Huang Qifa inherited from Mr. Blind.
Clothed Daoist is an orthodox sect of physiognomy and feng shui, and naturally, there's a rule prohibiting the use of such sinister techniques to harm others — but in fact, Huang Qifa cannot really be considered a legitimate disciple of Clothed Daoist, as his grandfather was just Mr. Blind's close attendant and never formally apprenticed.
So Huang Qifa felt that he shouldn't be bound by the sect's regulations.
And this forbidden technique of extending life was something he learned elsewhere over the years — it happened one early morning when he was invited to Thailand, to advise a local General. During this visit, he met a witch doctor from Southeast Asia and learned this method from him.
However, this magic technique is indeed quite sinister, and even though Huang Qifa had mastered it, he had only used it twice over the years.
