I just tried it with my Retina and my Mac Pro - put an Office 2008 install disk in the Mac Pro, checked the DVD share box on the Mac Pro's system prefs and voila - it shows up on the MBP. Not that I want to install it on the MBP, considering Orifice 2011 is already installed, but it works just fine, exactly as they said in the first article. Didn't need any more detailed instructions than that.
Nice to know that installing things from disks easily is a possibility, should I need it. I really and truly haven't missed the optical drive with the Retina at all - anything that was installed on my previous MBP via disk was installed on this one via Migration Assistant, and everything new has been downloaded.