But the 5 Power Healing seems like the more likely variant to have survived. Realistically it's versatility and the fact that the standard weave can be fatal if the patient is too weak make the 5 power version much superior. And we've seen that the Talent is pretty common too.

I agree that Tower dogma is the most likely reason innovations are scarce and certainly the Yellow would not take kindly to a Brown or some non-Yellow Sister with a strong Talent playing with "dangerous innovations" ... The wonder is that Suana claims the Yellow is not all about Skill, but more about a passion for fixing and healing things ... If that were fact rather than Yellow propaganda we'd have seen more Healing Weaves over the last 3000+ years. Especially in years leading up to the Trolloc Wars when the AS where clearly more experimental ... Messing with ter'angreal etc...