Thank you Tom. Your simple screenshot solved the issue. The overlay method, or hack as James put it, is completely redundant now, in my opinion.
Eric's right - plans should be thought of as cuts through the model, just like sections & elevations, although this example was more than a case of just showing the background with the current layer combination. We should be able to have a similar marked distant area to which we can assign a specific layer combination, model view combination, pen set, etc. It would beat the pants off this ridiculously cumbersome and over-complex cut plane thing.
Let's get a true BIM environment already!
Hunter.