Phong shading looks funny when using Shader Pipeline Renderer
Consider the following images of the same object. The first is rendered using the Default Internal Renderer, while the second one is rendered using the Shader Pipeline Renderer.
(Ignore the fact that the first picture only shows highlights from one light source; That's a limitation of the old renderer.) Notice how the shape of the highlight in the first picture is smooth while the highlights in the second picture exhibit noticeable artifacts, exposing the tessellation of the rendered object.
I suspect there's something wrong with the interpolation of normals in the new Phong shader. Can you check?