totally depends on skin type, i use to have horrible acne lets see what would happen if i was lax with the routine now, if i go a night without washing i'm a mess and get those deep pimples and the surface isnt smooth and glowy, if you have normal or dry skin maybe it works but us oily chics have to be diligent...
as far as shampoo i'm black with an afro and i find the best thing is to wash 2x a week or every 3-4 days, i tried the no shampoo method and its not for me cause i use styling products and conditioner alone doesnt get rid of the residue although sometimes in between shampoos i may conditioner rinse if my hair looks dull but this is rare usually in the summer when its humid and the scalp sweats, i think the longest i can go without shampoo is 5 days and then i feel dirty