It's a smart way to at least make it a lot harder to take over a misconfigured domain this way, but like I said in another thread, I'm not sold on the idea that

It's a smart way to at least make it a lot harder to take over a misconfigured domain this way, but like I said in another thread, I'm not sold on the idea that this is their responsibility. That said, having some safe guards for a common pattern of misconfiguration is always good.