can not use USB device to install fedora-19-x86-64-DVD

[John Reiser]

> I successfully installed fedora-19-live-kde-x86-64 by USB key.
> When I install DVD , after choose language, it has one more step to choose
> install media, from sdb1(USB key ), iso image or network. It reported
> the sdb1 not available , but the system is booting up by USB key, [so why?]

Anaconda explicitly refuses such a case:
  https://bugzilla.redhat.com/show_bug.cgi?id=873647#c7
and also Comment 8 immediately following.

I believe that anaconda should accept it, but apparently this case
is one too many.