I'm reading the GPLv3 for a blog post I'm writing, and I'm a bit puzzled by something I found in the GPL FAQ:

You may not distribute these libraries in compiled DLL form with the program. To prevent unscrupulous distributors from trying to use the System Library exception as a loophole, the GPL says that libraries can only qualify as System Libraries as long as they're not distributed with the program itself.

(link to section)

The problem is that I can't see where the GPLv3 states this. I can see where it defines Sytem Libraries, but not where it says I can't distribute them with a GPL'd work - assuming they're not licensed under a GPLv3 compatible licence.

Thoughts?