I had a bit of confusion around this node as well as Eternal Nature node, I think this node is clear now but Eternal Nature states adaptive spell dmg in the description and is still shown as + spell dmg instead of + adaptive spell dmg unlike for example Rune of Awe.
So no redesign of the whole immobilize stuff… No love for the spirit thorn build. The item had huge potential but playing around the immobilize effect is just terrible both in feeling and mechanics no matter if you run it with teleport ring or shapeshifting.