When a questionnaire is sent out to a group of interviewees, the first complete response marks the task as completed. As long as the questionnaire has not been completed, all users can see the answers provided so far. A Questionnaire Scheduler therefore only sends out a single task shared among all users of the Interviewee group.
In the sense of a true SURVEY management, it would be desirable to be able to set a flag with the questionnaire scheduler that modifies the workflow and sends out SEPARATE tasks to the Interviewee group A single Questionnaire Scheduler would then allow to collect independent responses from all users in the Interviewee group.