No difference. Both, in Schutz they are called "good dogs". Something is purely genetic. Large well structured teeth were always valued in the GSD working line, but jaw muscles can be strengthened through training only. When your puppy is 3-4 months old you leave him a bone to munch on, play war-of-tug and introduce to Schutz protection. Smaller GSDs are known to hold for longer, it is easier to lift them due to their waight, and they are better jumpers. It depends on your dog's temperament and drive, experience, experience of your instructor, the helpers, the decoy, everything. Many thing can put your dog off bite. Seemingly simple question requires a complicated answer.
Last edited by David Taggart; 01-04-2014 at 02:42 PM.