You're right in some ways, unfortunately there isn't a relevant past example to look to. But it is relevant in the sense of M$'s crappy record when it comes to security in their products and combating piracy. And MS tried to stop the pirating of Windows with their lame authentification checks with the release of SP1 and failed.
Also, MS stands a lot more to lose with the pirating of Windows than they do with Xbox Live. Not only does Windows cost a lot more, but even hackers and cheaters still have to pay for Xbox Live before using it.