i would suggest playing with the softness/hardness of the normals of the edges on the lower leg before resorting to adding geometry. It may be a quick fix.
Hello PC, attempting to make a dragon themed throne room ( yeah I know ). Currently fighting with a lot of concepts, will post something soon. Soft: Zbrush Maya PS Unreal Substance?
Hard to say without knowing what soft you're using. At a guess, I'd say .5 means 0.5 texels/unit, whatever your unit is. Assuming mm, It'll scale up/down your UVs so that the surface area of the mesh is at .5 texels per square mm.