Value for design time user control lost on postback

[rowe_newsgroups]

A quick an easy question that has me stumped:

I created a simple web user control that is basically a custom bound
drop down list. If I add this control at design time, it's value is
lost during a postback, regardless of the EnableViewState setting.
However, if I use a placeholder and add the control in the Page_Load
event handler, it works as desired.

What exactly am I missing here? Shouldn't the value restore the same
in both scenarios? Or do I misunderstand how ViewState works?

Thanks for your time!

Seth Rowe