But that still doesn't answer the question about getting blues from blacks. Sure, I can see some brassy birds show up from time to time but unless you have a blue bird, you can't get blues. Look at any other breed of chickens that is black, do they ever get random blues from breeding 2 blacks? No, because it can't happen due to how the genetics work. If it did, there would be blue australorps and blue javas coming from pure black pens. The color blue in this case showing up in a black flock has nothing to do with showing birds, it is just a basic understanding of simple genetics.
I don't mean to sound like a jerk but I only argue when I know I'm right.