Here's my understanding of it, and I'm going through it right now so please someone correct me if I'm wrong.
The main thing for a puppy is to recognize the difference between biting and mouthing, for GSD specifically you need to teach them never to bite, but mouthing is part of growing up (not only are they teething in a lot of cases, but they use their mouths to explore the world). I will not allow a hard bite or mouthing on my wife or kids, but I will allow mouthing on me, and of course on toys. I normally train positively with negative punishments, but this is one of the only areas where pup gets a bop on the nose for nipping at the kids or wife. As always, timing is key, if I wasn't there to see it, I can't correct it, which is also why my puppy is basically always tethered to me.
None of this should have any effect down the line on being able to train your dog to attack, since that's a different bite to her. Biting as a puppy is either playing too hard or fear/defensive, the biting you'd be teaching her down the line is protection, they're definitely smart enough to know the difference.
"Judge a man by his questions, not his answers" -Voltaire