I think that painting in black and white separates clarity from confusion. I rarely paint still life, but I love looking at it when artists I admire paint it like Chardin, Manet, Morandi, Matisse, etc.. Still life is historically ranked the lowliest genre of painting, certainly the genre closest to the earth which means there must be something to learn from its practice! Here is a still life painted as a demo for a student. Something I believe is important if you are painting representationally is to be able to express in your painting a 'feeling' of things having color and being in light, but without using any color, just black and white. Pulling that off, that is clarity. Look at a reproduction of a Raphael or Degas in black and white, the painting still works, you can even guess the color of things. oil on panel, 12 by 16