If you've used DataTemplates in Silverlight 2, you've noticed that when defining it in a resource of a control, the attached event should be placed in the .cs file containing that control. If it's a UserControl, it is logical for it to be in the usercontrol's .cs file, usually either coding for that event in the user control itself or exposing the event as an event exposed by the user control. So far so good, but what happens if we have a general DataTemplate that is used in multiple...