I'd imagine that would result in a slew of false triggers, because one can slightly vary the angle or pressure of their touch without intending to invoke any ki

I'd imagine that would result in a slew of false triggers, because one can slightly vary the angle or pressure of their touch without intending to invoke any kind of secondary action. One of the reasons I like the implementation of 3D Touch versus e.g. long press on Android is that it's a deliberate, positive input.