Alpha Pack Theory is a crock
When I first looked at Dog Training when I got my first Siberian Husky ( a notoriously hard to train breed) 15 years ago, I started looking at Dog Training, and very quickly came to the conclusion that the only scientific basis for any training methodology was a study from the 1940s that was so inaccurate that the author retracted it a year later, and spent the rest of his life trying to correct that mistake.
Not only was the study wrong, it was on the wrong species. Dogs and wolves do descend from a common ancestor, but their behaviour, especially around humans is vastly different.
And yet, famous dog trainers like Cesar Millan emphasized how the human must be the “Alpha Pack Leader”, and display dominance behaviour like stare-downs, always going through doors first, and flipping a dog onto it’s back in the mistaken belief that a dog always wanted to be “the Alpha”.
This has varied results when actually training dogs, and Cesar Millan never showed his failures. In some cases, it would scar the dog for life, but for some reason at the time, there were no studies that I could find that would compare methods of dog training.
Luckily, animal behaviourists in the past 20 years have done a bunch of studies of dog training methods and discovered that, yes, dog training methods based on one poorly designed study in the 1940s are not nearly as effective as positive reinforcement and consistent, predictable behaviour.
Hank Green gives a very good synopsis here: