John Jarrett touched on your solution.
In FOSI, you can create Editor and Print-specific attribute tests for you code. Without the test, the formatting applies to both. Also, Suzanne (obviously being Suzanne) is right in that boxing will not show up on the Editor view, along with several other formatting functions such as right indent values and rules.
Create a attribute test for the Editor as follows:
<specval attname="editor-only" attloc="system-var" attval="#ANY">
Create a attribute test for theComposition outputas follows:
<specval attname="print-only" attloc="system-var" attval="#ANY">
For anything in the FOSI that you want to be affective for one or the other, this is the way to do it. Using this technique, you can have your authoring stylesheet AND composition stylesheet all in one. I don't think the help system mentions the "print" side of this code, only the editor-only part.
Hope this helps,