Quote: ok not sure what you mean by breeding to blacks and getting 25%...
for bbs you get the following:
Black to Black = 100% Black
Blue to Black = 50% Blue, 50% Black
Blue to Blue = 50% Blue, 25% Splash, 25% Black
Splash to Black = 100% Blue
Splash to Blue = 50% Blue, 50% Splash
Splash to Splash = 100% Splash
if you breed lavender (lav/lav) to black (Lav+/Lav+), you'll get all blacks split for lavender (Lav+/lav). it's recessive, not dominant like the blue gene. breeding a split lavender (Lav+/lav) bird to a (visibly) lavender (lav/lav) you'll get 50/50 (lav/lav & Lav+/lav), lavender to lavender 100% lav/lav.
breeding lavender to blue, you'll get 50/50 black and blue, all split for lavender.