a. Who am I not biased for at the expense of black people?Recall your insistence than Prince was the greatest musician of all time? Or was it guitarist? Both? That's and the Williams sisters are but two examples. I don't have time to cull through years of posts to find others. I do think you show favoritism toward blacks, and that is likely the root of your over-inflating the importance of the Williams sisters and their story.
As for the second part, I already answered it. If you mean biased in a folksy, "I'm for all people" way, then the answer is yes. You can't be for all people without being for black people. If you mean it in a literal sense, then no, you can't be biased for all people and biased for black people. Being biased for black people would mean that you are by definition not biased for non-black people. Why is this question of such significance to you?
b. Agree to disagree on your second part. Fundamental difference breakthrough.
You cannot be biased for all people WITHOUT being biased for black people. We just have a difference of opinion. Thank you for finally answering that question.