You are doing the sequence correctly? First a rune attack, then use “Static”. The reduced cost won’t be counted for the rune you are activating it with.
it,s worst enchant for healing. One year ago, was a enchant “% of Health when you damage with rune attacks”. in helmet. It was OP. Other: “% of Health to damage” in multi hits rune attacks was OP.
Right now for healing… In Fatality… in Kill… in dodge… I prefer in fatality because it´s usefull to charge attacks and rune attacks. But if you have a Stamina build, then you prefer health in kill, or to bosses in dodge perhaps.