Each listed control read and parsed its properties part again, and every read is charged to the
package's 1 GB budget, so a file whose controls all named one part spent the budget on it: the
controls after that were dropped and the parts read later (notes, threaded comments) failed with
TooLarge. The parsed part is now cached by target; a part that fails to read or isn't a
formControlPr is cached as nothing and not read again. Test: 13,000 controls naming one 200 KB
part keep the sheet's 10,000 controls and the note read after them.