Changing Secondary Actor Elements

Consider the following description:

If the user wants to change the secondary actor of the first event to Student, simply click that event's secondaryActor field. The following dialog appears:

Committing the above data will change the description as below:

However, of course that does not make sense. To clear the data just registered for that event, click that event's secondaryactor field again, get the dialog:

This time click Reset and that will clear the secondary actor elements for that event. The description changes to:

NB: It does not make sense for an actor to interact with itself!