-Currently unimplemented. I don't remove invoices because there would then be
-no record you ever posted this invoice (which is bad, no?)
+This method now works but you probably shouldn't use it. Instead, apply a
+credit against the invoice.
+
+Using this method to delete invoices outright is really, really bad. There
+would be no record you ever posted this invoice, and there are no check to
+make sure charged = 0 or that there are no associated cust_bill_pkg records.
+
+Really, don't use it.