Not trying to interpret or defend the writing but I think it was not meant to say mixing bulldogs to other breeds make harder biting game dogs. I think it was suppose to say mixing bulldogs to other lines makes those lines harder biting dogs. Like hog hunting. A completely game, hard mouth 33lb pit dog can only do so much with a 250lb. boar. I am not saying it can't be done or hasn't been done but the lack of size can be a disadvantage to the dog. The cross he mentioned was to add the bulldog abilities to the larger dogs so the larger dogs (mastiffs, Johnson bred AB's, ) would have the bulldog traits. The desire to stay, the ability to hang on, and the weight to make it all work on something that weighs four or five times as much. That is the way I took it. EWO