Ok, so here is what I think has happened. Someone, not naming any names here...hahaha... apparently opened a template with a newer version of AutoCAD(2013 or 2014) and "overwrote" the default "acad.dwt" using the new program. Then, downgraded back to AutoCAD 2012, but still using the "acad.dwt" created with the newer version. Consequently, I can not purge the "Phantom" linetype because it is tied to a "section" style that is a new bell/whistle in the newer version. So, I have to find a way of getting this cleaned up without ticking off the IT guy to ask for a clean install of AutoCAD 2012.
Too many chefs in the kitchen....
I will see if I can work this out.