It's a skinned mesh, with my modified standard shader, with material slots set: Albedo, Specular, NormalMap, HeightMap, and my 6 custom ones. I'm using a modified StandardSpecular.shader.
I'm only using 3 of the 6 tex2D results, and my modified code lives in UnityStandardInput.cginc under Albedo() function. My BuildTarget = iOS and editor Graphics Emulation = OpenGL ES 2.0, viewing in Editor and GamePlayer windows.
When I add 6 additional texture tex2D() samplers to Unity's standard shader, the Normal Map (and detail) I have on the Mesh's material visually disappears.