The french poet Paul Valery observed, "To see is to forget the name of the thing one sees." This is a perfect expression of the mind-set for rendering.  Something has to shift. Maybe it's a shift from left brain to right brain; but that shift seems absolutely necessary to create a strong composition.  Until the shift is made and you start thinking in abstract masses on a rendering scene, you are, in sense, on the outside of the rendering process looking in.