In any case in which the presiding officer is to issue an intermediate decision, such officer may permit the presentation of oral argument when, in the presiding officer's opinion, time permits, and the nature of the proceedings, the complexity or importance of the issues of fact or law involved, and the public interest warrants hearing such argument. The presiding officer shall determine the time and place for oral argument, and may specify the issue or issues on which oral argument is to be presented, the order in which the presentations shall be made, and the amount of time allowed each party. A request for oral argument before the issuance of an intermediate decision shall be made during the course of the hearing on the record.