Well, to each their own. IME, and the experience of my mentor, there is no correlation between aggression/fear and a tied/tethered dog. The whole "it makes them aggressive" campaign is pushed by HSUS and other societies of the such like PETA and a few others....but they have little to no science to back the claim. The anti-tethering campaigns also offer alternatives to chaining, and say zip lines are better...which to me makes no sense. Lol. Both methods offer a dog a place it can go, and a place it can't. But, like I said, I have not seen and my mentor has not seen any direct correlation between aggressive behavior and a chain or being an outside dog. Theres no science or behavior analysis to back it.