That's not "dilution," that's the interaction of the blue gene with the background color of the hen's egg.
Blue eggs are blue gene + white layer
Blue-green are blue gene + tinted layer
Green are blue gene + brown layer
Olive are blue gene + dark brown layer
So, in successive generations of breeding to non-blue-gene chickens, you get
Purebred blue, such as an Ameraucana --> green (blue + brown) --> 75% green and a 25% chance of brown (because the blue gene has been lost).
in the homozygous EEs, which are green layers (they're brown layers + blue egg gene), you get green --> green --> 75% green and 25% chance of brown.
Autosomal genes work in a predictable way and they either exist or they don't exist. Very, very few behave in a way we'd call cumulative or dilutive.