Here is a fuller quote of a section quoted earlier.
Marriage and family therapy for instance, has to be so conducted that the “interpsyche” of the entire group is re-enacted so that all their tele-relations, their co-conscious and co-unconscious states are brought to life. Co-conscious and co-unconscious states are by definition such states which the partners have experienced and produced jointly and which can therefore be only jointly reproduced or re-enacted. A co-conscious or a co-unconscious state can not be the property of one individual only. It is always a common property and cannot be reproduced but by a combined effort. If a re-enactment of such co-conscious or co-unconscious state is desired or necessary, that re-enactment has to take place with the help of all partners involved in the episode. The logical method of such re-enactment a deux is psychodrama. However great a genius of perception one partner of the ensemble might have, he or she can not produce that episode alone because they have in common their co-conscious and co-unconscious states which are the matrix from which they drew their inspiration and knowledge.
Psychodrama Volume 1, 4th edition, page vii