Hehe
Our golden retriever had to wear one a few months ago. It was so sad - her tail must've stayed between her legs for a good two days.
She'd go to walk through a door and catch one of the edges against the door frame. She'd then spend the next several minutes standing there motionless, with an Eeyore-depressed look on her face, until we 'unsnagged' her. It took her 3-4 days to work out that she could just back up and try again. She's a smart one, alright
btw, your link goes to the same photo that's in your post.