The video tells you how you meet people if you have a dog with you. The trainer forbids anybody to touch their dog unless that person has permission to do so. It is disrespectful of the dog and the owner/human companion, to touch a dog without both the dog’s and the human’s permission. Some people think it is a complete invasion of privacy. There’s more to it than that though. You want to make sure that if you approach a dog with an outstretched hand that the dog accepts it. You are a stranger to a dog. They might react badly. So you want the whole interaction to be controlled and manageable.
It is said that if you have a dog on a lead with you and a person approaches who wants to touch your dog you should be polite but direct about it. You should tell them exactly what you want. If you don’t want them to touch your dog you should say so, but politely. One person says that she insists that her dog is either lying down or in a sitting position before he can be petted. This is to do with training. She wants to make sure that her dog realises that people cannot pet him until he is in one of these two positions. Otherwise she believes that he will jump up eventually onto a person and as her dog is very large he may hurt them.
Common sense says that a dog might not react well towards a stranger who believes the dog is friendly and wants to be petted. It’s a bad presumtion to make. And as mentioned in the first paragraph it seems that experience dog owners find it plain rude if a stranger wants to pet their dog. You wouldn’t do it to a baby and therefore you shouldn’t do it to a dog without asking permission first.
If you are given permission you should approach gently and allow the dog to sniff you. Personally I just present the back of my hand to allow the dog to sniff it. You should not lunge at the dog with a waving hand. That applies by the way to approaching a domestic cat that you have not met before. Domestic cats can treat hands like that as prey items to be bitten.
And you should keep the meeting brief and not overdo the petting session for obvious reasons really because you don’t know how a dog will react. The whole process should be done with respect and caution. The guy in the video is very strict about it as I’m sure you will agree. I guess it’s better to be that way than the other way and have your dog bite a stranger causing a huge amount of distress and problems including potential litigation and compensation!