The thing is dogs are living creatures, not golf balls.
In theory Sabi was not the pup I would have selected, and in practice she lacked the drive to be a great working dog. She was a quiet pup, a thinker. You could see the wheels turning at 7 weeks. She watched everything, and I do mean everything. She wasn't given to the normal puppy outbursts or foolishness, but she was fearless and adventurous. In theory I would have passed her by in selection. She taught me an important lesson. There is an essential something about some dogs that is not quantifiable. She proved to be the best dog I ever put hands on. I could have sold her a dozen times. My boss swore the only flaw she had was that he didn't own her.
You can only use a clipboard so far, the rest is instinct and sometimes just luck. You can study the genetics, you can rate the responses but the rest is seeing, really seeing, the animal itself.
And a 12 gauge? Trans Am backfired next to Sabs and Lex when my hubby tried to start it. Sabi was about a year old. Sabi moved closer, didn't even flinch. They don't require exposure, sound sensitivity shows early.