Lavender and chocolate splits genetics question

[Ivy_Chickens]

Okay, so I ran into a question that stumped me. I wanted to breed some splits for my chocolates and my lavender orpington flocks, and thought I'd be clever and instead of putting a black orpington in with them, I'd just mix the lavender and chocolates. It made sense in my mind. Both genes are recessive and both work on a black base, so I figured a chocolate rooster over a lavender hen should give me a few chocolate pullets split for lavender and a few black roosters split for lavender. So I get two splits in the same pen. But then I became stumped. What happens if you breed two splits that carry both the lavender and the chocolate gene? For example, if I breed a chocolate roo to a lavender hen, he should give me chocolate pullets split for lavender and black cockerals split for chocolate and lavender. If I breed those splits together, some of them should get a lavender and chocolate gene, which to my mind means some sort of double dilution similar to mauve? This is confusing me because mauve is blue or a splash mixed with chocolate. These are all dilute genes, so what am I missing?