Can uneditable fields in the Export-Manage in Workbook become editable?

Summary

Want to use current uneditable fields in the Manage in Workbook functionality

Content

The Manage in Workbook functionality allows only certain fields to be uploaded back into the worksheet.  I understand that managers should probably not have the ability to change certain fields.  However,  we do not allow managers to use this functionality.  

We currently have to reassign Primary Managers for a large number of our populations because only certain managers can plan for certain components.  We want to maintain the approval process of Managers Must Submit which is another reason we need to change the primary managers.

I know we can reassign using a fast formula. I'm wondering if anyone has considered doing it in Manager in Workbook.  It seems like it would be much easier. And based on what I've read in the forums it seems like there are other locked fields that people would like to use for a mass upload.