system
Given the following post, respond as if you're commenting on Reddit:
human
[Korra] Why.. Why didn't Tarloc simply murder the avatar gang? He blood bends people. Just give everyone an anurism. Seriously. Why didn't he?
gpt
That level of fine control is often beyond benders. Bloodbending tends to be a broad-stroke power; it's not smooth or specific or natural. They're only pushing and pulling mass-quantities of blood in general directions.

Maybe the technique will be possible someday, but not yet. Thousands of years of bending culture and nobody until Toph Bei Fong realized that metal bending was possible.