Just deferred decals isn’t what I was referring to but rather using the deferred decal materials applied to custom geometry that would snug over other static mesh geometry. This is an older Crytek tutorial but the same things they’re doing with custom-built geometry for the decals works with their deferred decal materials in the latest builds:
http://docs.cryengine.com/display/SDKDOC3/Using+Decals+for+Destroyed+Structures
Notice how they build little floating meshes that wrap around the corners of the broken pillars or snake all the way around the edge of the concrete slab? That’s what I’m asking about in Unreal with their deferred decal materials (so you could have a decal that snakes around but only applies new normal information while leaving the diffuse and spec the same).