My friend prevents using his stacks on SS and he have no problems at all.
The free succor chance is almost insignificant since succor heals almost nothing compared to other AOE heals(without mentioning the mana cost),and the chance is low you can't rely on it.
Massive 10%? If the boss hit you for 5000 it nullifies 500,and if it is an AOE 5000 it nullifies 500 for everyone ,i don't see the big deal of it... everyone will still receive 4500 dmg and thats a big amount to be healed with an 150 potency aoe heal (i know you will have another healer on 8 player but still...)
What i'm trying to say is,20% would be a good buff, it woudn't make it OP. Is that asking too much?
I'm trying to make everyone understand, it is such a "big" skill and it deserves some buffs,some mechanic changes, a LOT of SHCs complain about SS because most of the times you use it you don't feel like you're helping at all everyone still receives gigantic damage.

Also ty for replying everyone