Those dogs are quirky. They abuse a sort of side-effect of physics layer shenanigans. As a result, some weird behavior will emerge under the right (or wrong) circumstances. You can sometimes swing them around. I knew about this quirk a long time ago, and deliberately used it here, because I was hoping it would make people laugh. I'm thinking it just doesn't get a chance to happen that often, though. Try letting the dog "bite" for a half-sec of sitting still, and then turn in place. Sometimes they will "stick" to the collision point, and you can swing them around the bot. My intent was for that to simulate them sinking their teeth in and not letting go in a funny way.