That's just it - I couldn't determine the layer to just shut the stupid thing off! There are over 200 layers in the reference file alone, each in varying states of on/off, plot/no plot, frozen/thawed. And the layers had names like 482736oshgjvke-ex. WAY too many to start fiddling around with some trial and error. I've been having other problems with this drawing as well - regen taking forever, ACAD freezing up like crazy, etc. The set's going to QA/QC tomorrow and I needed it done.
And BTW, Matt, I did feel a certain savage pleasure in openly defying a Cardinal Sin of AutoCAD....
so hah!