Herding Aussie?

My friend has an "show quality" Aussie (apparently the breeders just wanted to breed their show quality female with a show quality male for the heck of it) and at the beach, and I know, I've made a rant about this but I have learned to leave it alone, his interactions with people his owner claim to be his "herding instincts".

I am unsure. I've been watching videos of Aussie's herding for the first time, and I was recalling memories of my working stock Aussie, and I couldn't agree that was the instinct her dog displayed.

What he will do is that he will see people, freeze, and start huffing, then growling before he runs up to them barking. He will be in front of them then stop and look at us, before continuing to harass the runner. I honestly don't see his behavior as real herding instinct, I feel like it's more insecure in actuality. Our Aussie didn't partake in such behavior, my grandmother's Aussie didn't partake in such behavior. I've been hearing different comments on the views of how Aussie's herd, and when my friend hears them she'll either say their wrong or, in a way I think is rather pretentious, say, "Well, he never went by the books to begin with."

Could someone link me to a few reliable sites about Aussie herding and their behavior? I looked at some already, but I would also like to hear the views of experienced Aussie handlers? I'm interested in pursuing a life with this breed personally, as it could be considered the "foundation" of my love for dogs, and I want to be sure that I'm not unrightfully getting worked up over something I don't understand, when I could. I would just rather understand their herding behavior and if there are different ways for the different individuals.