Unfortunately, even pretending, there is nothing that a BYB dog has to offer over a reputable breeder. If dogs aren't titled in conformation, that doesn't necessarily make the person a BYB. A BYB is someone breeding for profit, without much knowledge of the breed, health concerns, etc. A breeder who doesn't do conformation, but finds other ways to prove their dogs is just a different kind of responsible breeder. (Breeding a farm working BC, for instance, would not be a bad thing, even if the dog lacked conformation or herding titles, because the dog is working for a living and proving itself in that manner).
I would hope the person breeding the healthy, moderate GSDs you are "buying" in your scenario would be doing some kind of performance, like obedience or agility, or maybe therapy work (very admirable). Then they would be proven as performance dogs and your BYB wouldn't actually *be* a BYB, just not a conformation breeder.
And actually, I have a BYB dog (my fiance's Westie). His parents both have health problems (dad has allergies, mom has a soft timid temperament - very bad for a terrier). So our dog has dad's allergies/chronic skin problems and mom's timid temperament, making him a fear biter and resource guarder. He is physically and mentally unstable. Since I'm living it, I could never imagine someone doing KNOWINGLY (even if we are just pretending).
