The previous descriptions of workers seem very fair to me. However, I have Rufus. Father working dog with gamekeeper on Goodwood estate, mother worker kept more domestically as pet (but kennelled), and worked at weekends. The second training class I used was run by GSD breeders who bred for the police and competition obedience, and show. Before going to them, I used KC foundation classes. Rufus failed twice and was known as Rufus the Reprobate. The GSD trainer described Rufus as off the wall at 15 months, but did help me work wonders on down sit, come, and stay.This, however was inside a scout hut! I started agility to help Rufus begin to focus on me. He was much more wayward than the other dogs, and was the only dog in 10 years to find a gap in the fence when he saw a rabbit go by. He is now quite good, but I have to slow him down for accuracy on contact points and weaves. I do think Rufus's instinct may be a bit of throwback genetically. He caught his first rabbit at 5 months, and so far this week has caught a pigeon and another bird. He is 4 and a half. Despite his extremely strong hunting instinct, and lack of biddability, he is calm and affectionate at home (until he sees a creature out of the window). I am sure with your experience you will find it much easier and quicker than I did.