Gujarat High Court Civil Manual (subordinate court practice), 1960
The attention of Courts is drawn to the provisions of Order XVIII, rule 4, that witnesses are to be examined in open Court. The power under section 30 (c) (and see Order XIX, rule 1) to order any particular fact or facts to be proved by affidavit or the reading of an affidavit of any witness at the hearing, should be exercised only in special circumstances, or, as that rule declares "for sufficient reason", which should always be specified in the order; there can be no general order for the admission of affidavits in suits or appeals.