Getting rid of unused vertex attributes?

I’m currently working on a terrain system that uses static meshes instead of heightmaps.

The terrain macro normal is baked on a simple plane. To look correct in the engine, i simply ignore the vertex normals in the shader, making them useless.
I also know the size, position and rotation of my terrain tiles, making UVs entirely useless too since i can easily create them in the shader.

My mesh only need to know the xyz position of the vertices and nothing else. Is there a way to entirely get rid of the UV and normal attributes of the vertices to save memory? (i guess this would save vertex transform cost too).