Mesh Decals - reduce UV Channels

GhosTDoG

I use the main mesh and the decal sheets within a blueprint (components) - just a simple prefab.

The mobility of the main mesh is set to static, the mobility of the decal sheets/trims is set to moveable, so I don't need a second UV channel, when I use static lighting.

As far as I understand dbuffer decals get multiplied in UE4 with the subjacent materials (mesh) and ignore baked lighting on itself?

I can't see a difference, neither with the decal meshes set to static, nor to moveable - in both cases the decal materials (meshes) receive shadows, if I bake the lighting.

But I'm not sure if this way of saving an unnecessary second UV channels is correct or will lead to shading/ lighting issues in a  more complex scene?

Thx

GhosTDoG

To simplify the question...do I need a light map uv channel for the decal meshes?