Train and educate the dogs is the best way, ever!
About biting : only few csw are able to do schutzhund, because many are able only to growling and barking, but when you leave the leash...fly away till the horizon!
Obviously the dog should be trained, even to bite, but many csw -simply- don't have the right character to do this.
Our dogs bites quite well, but at training field we see many problems with other csw...may be the character, may be the wrong training (they cannot be trained like a GS)