Did you ever find a solution?
I recently did some testing on single part file size and was blown away by the impact of "save_model_display" coupled with "shade_quality". Parts could go from less than 1 MB to over 46 MB just by changing these two values. I have not had a chance yet to test the effect on assemblies. Below is part of whatI posted over on the PTC community.
I just finished extensive testing of several different model display settings and their effect on file size using WF5 M120, WF5 M160 and Creo 2 M050. Here is a summary.
I have attached a PDF copy of the test data. What becomes quickly apparent is that, depending on config and display settings, file size can range from less than 1 MB to over 46 MB for the exact same file.
Something else that may not be obvious. If "save_model_display" is set to wireframe, when the file is previewed in Pro/e or opened in Product View (Creo View) it will only be visible in wireframe mode. If the file was saved with "save_model_display" set to anything else, then preview and Product View can display the model all four ways (shaded, no hidden, hidden, and wireframe). Also, the active display mode when the file is saved has no bearing on what is stored in the file.