In few words I could explain the term Visual Continuity as a continuous focus of elements in a visual context of a specific action.
To complete an action we could do several steps. Between two steps there could be a passage through visual elements.
That is where we have to do something to guarantee the attention of the users. To satisfy the users we had better think as a user.
I would like that an application continuously gives me feedback without making me wait too long for a result. A progress bar is better than nothing. The point of view of the user is very important in order to have success with one application.