Just because a lab is yellow and black doesn't mean it isn't a lab. (As you it said it IS unlikely). Show quality is not the same as pure bred. A pure bred animal can vary from the standard in all sorts of ways, but it is still pure bred! That, I think, gets to the heart of the dispute in Americauna/EE dispute.
Now, if you'll excuse me, I'll show myself to the door....
A pure bred animal can vary from the standards in all sorts of ways? According to who?
If an animal does not meet the standards, how can you call it a pure bred animal? The standards are what establish what the breed is.
Why don't you try telling people that a Rhode Island Red with white spots is still a Rhode Island Red. People would laugh at you.