Maybe the ones I've been around just had obsessive owners who ended up training them well. One of the Weimeraners named Orwell lived with a buddy in a rental house without a doggy door. Tom taught him to open the door for himself (normal round doorknob, no handles) and even paw the deadbolt until it flipped down and unlocked. It was cool to tell him to go get the paper off the porch and watch him do that stuff. Of course, Orwell figured out how to open the fridge, too, and Tom didn't think that was nearly as funny as I did. It only took me a couple minutes to teach him that while Tom was in the shower, too.