Jen,
Please don't get frustrated, but the fact is that blue (Bl) chickens don't breed true. You can qualify it and say that they theoretically breed true 50% of the time or that they don't breed true 1//2 the time, but since they don't breed true (as in always) then they don't breed true (according to the definition). A simple Punnet Square will prove it.
Here are just a few sites that address the subject...
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Since we are talking about poultry, and specifically breeds accepted into the APA/ABA Standard - ie. Ameraucana, breeding true is defined as the APA/ABA accepted definition; ergo, "breeding true" is accepted as valid if like bred to like produces like at least 50% of the time.