I wondered that too.  Sometimes random posts are actually ads but this one looked like a YouTube video. I didn’t view it.

That’s chip’s dog. The video is from a few months ago.

Is that Chip who posted it?

Idk.

A mystery.

Don't people use muzzles to proof true aggression or check it?

Yes, for either.  Usually to keep the dog from biting or remind him it’s not something he needs to be doing.  

I muzzle trained my lab due to his issue with eating things he shouldn’t. I was paranoid for awhile after his blockage surgery. He doesn’t wear it now and it doesn’t even fit him anymore. 
 

If can be helpful for dogs who aren't great for grooming or vet visits. It’s better if they’re conditioned to it so it doesn’t add to an already stressful visit. Same thing when working with reactivity or aggression towards people or other dogs. 

What caused the blockage?  I don’t like muzzles as it doesn’t take the fear away. But if a dog is going to bite, they need one.

The point isn’t to take the fear away, the point is just to keep everybody safe while you work on training. Properly conditioned dogs do not mind muzzles and some will even get excited when they come out because they know it means good things. Barring some sensitive dogs who may always have a hard time with them.

Muzzles can also add a confidence boost to the handler even if they’re not aware of it which can influence the dog as well. Handler anxiety etc. can ramp up or cause the issues. I have seen a lot of dogs that way. 

Muzzles can be a great tool, particularly when fitted properly. There are plenty of dogs with pika who are also much safer for having them off. 

blockage was either some trash he found after the snowmelt and ate it, or it’s possible somebody put something in my vehicle when he was in it. There was an odd mix of copper wire, wool type stuff, and a type of plastic I don’t have in my house. I later found some of that wool in my vehicle and since he was kenneled there’s no way he could’ve gotten to it and I don’t know where it would’ve cone from. 
 

I was lucky the wire was in there because the plastic was what was causing the blockage but the wire was what showed up on the x-ray and made the vet decide to operate. He likely would have died otherwise.