The da you use doesn't know what the color of the paint is. That has to be the lamest idea I have ever heard hands down. The pc you have will do fine on dark colors. Don't limit yourself to a single brand of compounds , pads and polishes. Try trading samples of products with friends and other forum members. This gives you unlimited choices without buying a ton of stuff you may not need or want. Here is a link for a service that you may want to consider. I'm not knocking Adams but decide for yourself if there is something else you may want to try.
http://www.thedetailbox.com/