We had a radio button that would not trigger the Click.Command event and eventually determined why: the buttons were in a StackPanel with no containing ContentControl in sight. Wrapping the StackPanel in a ContentControl fixed it. We examined our other
buttons and found that in every working case, the buttons were contained in something that had a ContentControl in the template (e.g. BlackLight clipping border) or itself was derived from ContentControl (e.g. ScrollViewer).
I did a modicum of digging around to see if this was expected behavior or at least known behavior but didn't find much. Would you consider this a bug? Is there any good reason why XAML declared command bindings in a lonely little StackPanel or Grid with
no ContenControl shouldn't get parsed?