This is similar (but a simpler version) of suggestions I have made earlier.
It is (would be) very practical to see very clearly on the Focus list which of the actions actually MUST be done today (have been agreed to be done today), e.g. appointments, and all the other actions that I have focused for some other reason (probably contextual or priority reasons) and which I might wish to unfocus.
Similarly, under Scheduled it would be practical in the same way to see the difference between calendar actions (appointments etc) and all those others (the vast majority) that are just regular GTD Ticklers, i.e. impossible to do before a certain date but not necessarily to be actually done on that first possible date.
The simple solution - also very GTD 
- would be to have a separate “type” for calendar actions (Next, Waiting, Calendar, Someday, Tickler). To show both Calendar and Tickler on a common “Scheduled” list is perfectly fine by me - it saves one list. The important thing is that we can tell the calendar actions from the ticklers.