Cesar Milan, dog intimidator
Gracie is a lovely, bouncy Labrador retriever who gets all excited over the opportunity to chase a chicken. Look at her at the beginning of the video: ears and head and tail up, eagerness and concentration in her facial expression, lively and quick movements.
Now look at her at the end of the video. Do you see a dog who is "happier because she's no longer obsessed" with chasing chickens? No. She's a dog who is stressed and fearful because some bullying, hissing stranger has just appeared in her formerly idyllic life. He's acting out his dominance/submission fantasies on her against her will and her formerly trustworthy family members aren't even trying to defend her.
Sure, you can control your dogs by thoroughly intimidating them, but why would you want to?