What's the deal with a straight tailed crawfish?

There is a saying that you shouldn't eat a boiled crawfish with a straight tail because that means the crawfish was dead before it was cooked. When a crawfish is boiled it curls up it's tail. However, if a crawfish was really cold or just near death before cooked, it may not curl up its tail and is still good to eat. The best way to determine if a crawfish was dead is to inspect the meat – if it falls apart, don't eat it.