Hi Gregory Klein,
We face the same kind of issue in our organization. It's correct that the signature, in some cases, will break, but we found two cases where it happened in our solution.
When we used VBA to copy and delete sheets, the signature would break at some point. The "funny" thing is, it's only sometimes when you execute those commands. So, you can't test and expect it to break, which took us some time before we managed to locate what caused the signature to break.
Our workaround was, of course, not to use those commands. Instead, we implemented the following workaround:
Copy:
Add a new sheet, and then copy all elements, text, ListObjects, shapes, etc., to the new sheet.
Deleting:
Rename the sheet to "Deleted_<A unique code of 6 digits>", and then remove all elements from this sheet, and finally make the sheet VeryHidden.
After this workaround, we have not had any issues.
Alex