Hi Jeff,
I wonder if this can be prevents by unchecking the Publish Form and XSN checkbox. That checkbox only needs to be checked when there is a change to the XSN (attached to DAT); the checkbox allows DAT to update the XSN in the ShP form library as well. So if your XSN is not changing, try unchecking that box. Of course, this doesnt full answer the question: if in the future there IS a change to the XSN, and you check that checkbox, your ShP form library columns will be modified again. I'll open an investigation item to check on what could be done.
Thanks.