This was because the Skill involved splitting off a piece of one's own Dao to implant in a junior. It wasn't about packaging a Technique as a life-saving tool; it was about giving them a part of your very Dao.
In other words, once you split off a part of your Dao, you could no longer use it, but the recipient would be able to use it to a certain degree.
Furthermore, if something happened to the recipient and the Dao Mark wasn't retrieved in time, the split-off Dao seed would be lost along with them. This would result in a permanent, irreversible injury to your Dao. Therefore, it must be used with extreme caution.
'Looking at the description of this Technique, the price to cultivate it just to protect a junior Disciple was clearly too high. To be blunt, it was downright idiotic.'
