There a number of issues with the display of multi day events.
Month view has got it completely right - the multiday event shows across all days on which the event is taking place. The mouse-over pop-up shows the start and end date/time of the whole of the event.
Where a multi day event spans more than one week, in week view there is no clear indication that there is an event there, other than by the shading of the background. Mouse over does display the event details, however that is not overly usable on touch screens. This applies similarly in day view where the day is not the start day.
Note that the mouse over details for the multi day events in day and week views only refer to the day being hovered over, not the start and end of the event, as per the month view mouse-over details.
In agenda view a multi-day event only shows on the first day of the event, not on every day similar to the month view. It is therefore not immediately (or obviously) apparent that a multiday event is taking place at all. On the 'up-side' if a multi-day event is in progress and its start date precedes the agenda's start date it is listed at the top. One then has to notice this and infer an on-going multiday event.
It would be much clearer if...
1. All mouse overs displayed the same details for the event, irrespective of the view - that is the start and end dates.
2. In agenda, week and day views, the event should be shown clearly against each day.
3. In day and week views, where a day is not the start or end date, maybe this could be shown as an all day item at the top of the day space.
4. If current functionality is specifically exploited by some users, then may be this could be implemented via a "Show all days for multi day events" option.
This idea has been addressed on the new timely web application. Try out during private beta at https://ww.time.ly/new
All plans are FREE during private beta!