Oh a couple more things. The blue breeding works the same for all chickens, they are only breeds in our minds. If you are getting your chicks from a blue and black breeding you will not get any splash so perhaps that is what is going on in your case.
As far as sexing day olds, I band all my chicks by breeding line and then I also make a guess at hatch as to the sex. I put band on right leg if I think boy, and on the left leg if I think girl. I make a guess whether I am feeling confident or not. Then as they get older you can see how well you did at guessing. My theory is that if I keep the ones for breeding that I guessed correctly, then I will be breeding toward an autosexing line. It is too early to say whether this is working but its a way to keep track of what your first impression was of the chick to measure against what it truly is. If you see a 6 week pullet with band on her right leg that is one you guessed wrong and you can remove her from the breeding line if you choose. .
Andy