Don't know Birdie or his dogs. But I have known a few heelers where a heel or stay command was as good as any leash.
Good examples of the herding breeds have a drive to learn and obey commands, I found all three of our heelers really easy to train, and in photos I have noticed they are frequently looking at me, watching for visual clues even when I weren't aware of it. That third one tho is too impulsive, she'll check immediately if I call her back but, try as I might, she still occasionally thinks about herding passing cars.
Of course, not all dog breeds are the same. IMHO the hound breeds are the worst when it comes to trainability, all they wanna do is run off and follow their nose, exactly what they were bred for.
