Thanks for writing.
The reason for this not being possible is the fact that almost all item controls on Windows Phone (native and third-party) implement a special UI virtualization mechanisms which reuse visual containers while scrolling/swiping between items. That said, if the content within your source is any visual element, you will get exceptions since Silverlight does not allow inserting a single visual element in two different parent collections which will actually happen if the elements within you source inherit from UIElement.
The standard approach of visualizing any data is defining a special Data Template that actually would have the structure of your Control
and binding the properties within this template to a propery on your business object which should be part of the source.
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