The difference is how we are looking at the terms. Line, blood line, etc... Confusion comes when we ( I ) start to breed the birds. One can always have, example Underwood bloodline, but what changes is how they are mated. Underwood sees a bird one way and is working on that goal/trait and the new breeder will see the same bird totally different and use it in a totally different way. In the long run, they change in many aspects of the line. One of the old time breeders and judges, Homer Endersby, used to say blood is blood but that doesn't mean that will out weigh a good eye.I still can't believe that if I take a 100% pure Underwood male and put him over a 100% pure Underwood female that it could be anything but a 100% pure Underwood bloodline chick. Now if this is true then the Underwood will always be. If not then I give up. I can't answer questions about any of my birds if I can't even say what lines they are. I don't only have one but the way you folks are talking, I would only have one.
Geez, this is totally mind boggling to me. lol
.
We can go on and on about the differences...basically it is how we the individual thinks of the terms...line...bloodline...etc.