I would take a guess that a huge percentage of bobtailed BMC's trace to Crook and folks just didn't know it or the papers don't show it. I do not consider bobtails to be a BMC trait, not to take away from Crook as he was a really good dog and produced some real good dogs, in fact one of my favorites was a grandson, a littermate to Williams Ben. I never bred him though.
Have you seen the parents to this crook dog? Or does it go back to far?