You can map the content controls and cross reference them so they work as one when checked and unchecked. The content control version of
http://www.gmayor.com/BookmarkandVariableEditor.htm makes this a simple task. If you want to explore what is possible with mapped content controls to a greater depth then Greg Maxey has a more sophisticated (but inevitably more complicated to get your head around) version which is linked from that page.
As for the content control/form field issue raised by Paul
http://www.gmayor.com/ExtractDataFromForms.htm includes a tool to convert form fields to content controls.