White, gray, and black

I had a hard time wrapping my mind around Roberta's attempt to explain her concept of the purity of souls (white, gray, or black). So as usual, I spent some time trying to find what others have thought of this. I found one (yes , that was one) person who actually made sense to me. This person had been to the other side (taking his/her words as valid) and during the return viewed the earth from a higher level. At that level there was a realization that all souls are white and will always be white. There is a shading but the shading is not of the soul but of the intent that motivates the soul during each incarnation. So depending on the purpose of a particular incarnation and the intent required to fulfill that purpose, it is possible that darker intents may make the soul appear other than white. Now that makes sense to me. Thoughts?