Nostalrius Begins - Quality wow vanilla realm (1.12)

So one of the great things I loved in Vanilla was having a shadow priest heal a dungeon through their vampiric touch spell or whatever it is that heals the party for a % of their damage. My question is, does +healing increase the healing from that effect? For example say I have some helm with +30 healing, will that increase the healing, or would I be better off just stackin shadow damage?