John,

>Logically, that does not make sense. Why would you show something in a UI element, such as a combo box, with no underlying value to represent the display value.
>
>Please give me a logical reason why somebody would do this.

Sorry to pop in here, but i think there are situations where you want to do this.

A great example of this feature is the zoomfactor combobox in the office applications. You can select one zoomfactor from the list or you can input your own without having to add it to the rowsource list.

In office the zoomfactor applies to every open window, but if you want to be able to define this to be variable for every form, I think you would have perfect example of the described behaviour.

Given this example it would not be hard to imagine other cases where it might apply.

Walter,