"Lower Resist Curse reduces an enemy's resistance to Fire, Cold, and Poison damage. It lowers their elemental resistances by a certain percentage. Lower Resist helps with elemental damage types, Blessed Hammer and Bone Spirit/Spear operate in ways that aren't influenced by this curse."
Im pretty sure I watched a video of MrllamaSC where he was playing a hammerdin and on switch had a lower res wand which he used on bosses.