Thanks for sharing your perspective!
I'm Asian, and I just think dogs are a great way to break the ice between people of all races. At the dog parks I go to here in Texas, I have had friendly chats with white people, black people and brown people.
But it's not just race. Gay dog people talk to straight ones. Women and men share tips. Older people talk with younger ones. It's one of the most democratic places, in a really good way.
All that being said... I have close black friends and they've related stuff to me that just appalled me. And made me realize there is a reason black people have to do that calculus you mentioned. Because unfortunately there are white people who, for example, have no problems with Asians or Hispanics but still don't like blacks. Some of them even voted for Obama and love Oprah or Kobe. I don't know why this is.