I took some methods of QDate, QTime and QDateTime that were previously just marked with \overload and gave this command its parameter: primary on the primary overload (a new feature in QDoc at 6.11) or the function name with either empty parameter list or the signature of the primary.
In either case, I got "undocumented parameter" warnings for the parameters of the overload so documented, that were not present before I added the parameter to \overload.
The documentation of the primary did, in each case, cover the parameters of the overload (as their parameters shared the name of its).