I don't know if I have anything substantive to add. However many years ago I found an online brochure for a Caribbean Island that specialized in this. They bred three types of dogs, Doberman Pincher, Rottweilers, and I forget the third. The deal was a single woman, or a couple either Male/female or Female/female could come to the island. They would be treated to a show and tell involving girls that would show proper technique. Then a dog would be picked out, and time would be given to acclimate the new O/owner(s) and the dog. Then at the end of the time (week or week end, I forget) The dog was taken home. Clearly the dogs knew exactly what was expected from them. In fact bred to this purpose.

The odd thing was...I found about this on an animal rights website. They clearly were against the idea.

I have long since lost the book mark for this, and have been unable to find it again. Nor can I recall exactly the website I first found this on.

I am sure the reason that single Men were not allowed to visit the island in question is, they would have been overwhelmed to the point of the island sinking. Okay a bit facetious there, but clearly they were trying to limit visitors to the O/ones truly interested and dedicated.