Paul,
Thank you for posting the example, it really helped clear up what the issue is.
I was able to see exactly what you were talking about and can see both sides of the issue. From the user standpoint it is super unhelpful and not explicitly documented anywhere that I could find. However, this behavior is the same for LabVIEW 2011 to 2014 and because you are not allowed to add controls or indicator to the pages of the type defined tab control, I am not sure how that type def would really know about the items that are on each page.
I couldn't find any CARs associated with this or documentation on what is supposed to happen. I'll try to ask some people tomorrow who might have more insight.
Matt J | National Instruments | CLA