Normal maps are pretty simple form Z, do a google about it.
As for animator friendly, not too sure what you mean about that. A normal can be shown in the viewport but I dont really se how that is much of an advantage unless it warps, but that is more of a modeling and blend shape issue as you may need multiple normals/dispa to compensate for the deformation driven off the blends
"No pressure, no diamonds" Thomas Carlyle