Lets say I have 1000 life and then 1500 after using Battle Orders.
If a Druid summons Oak Sage that adds another 50% life, would it calculate 50% off of the 1500 life or 1000 life?
That's why cta/max life runes aren't as effective on shifted druids. The bonuses from oak and all their shifted skills are added to the small bonusses from cta/runes.