you guys over there in the USA are well known for being in to "line breeding"
HAHAHA! You know what they say, when it aint broke, dont fix it. LOL!
On a serious note, a fella named John Wick bred brother to sister for 4 consecutive generations and never seen one recessive trait pop up that made the dogs unusable. He noticed that their performance never got no better nor any worse and he really wished that he would have went on from there to see what the 5th breeding would have produced. These were not lurchers though, they were coondogs. I have a gyp on my yard that is out of