First, in his definition, ps60s denegrates people who use the phrase; showing prejudice. He also contrasts between African-Americans and "whites"; also conveying prejudice.

Regarding the meaning, like other phrases, it has several. It is based on the context; just as the multi-use F-word. I often use it to mean that the given situation should be seen at face valus (the result), and not to be analyzed further.