To some extent, people warn you about the rage of dog's, but really, you should be more concerned with the fellow who taught it to follow hand signals mixed with emotional trauma. If you walk into a house and the dog is just barely making eye contact with you, and the owner is polishing a tactical vest, and talking to a pencil, the dog is not your greatest concern.

If you were to visit John Wick's pad, you wouldn't experience barking; you would experience silence, and then you would experience having no idea who you were. That's not a guard dog; that's a witness.

It's the same thing with the guy in the video. The dog seemed cool. The owner looks like he has a collection of restraining orders against emotions. If that dude told the dog to sit, the dog would be updating its resume and applying for jobs.

So yeah, if you hit a big dog don't freak out. Just check if the owner looks like he trains with the Navy Seals, and names his pets after Greek tragedies. And then freak out.