Discrepancies between Design and Blueprint previews

I’ve noticed that there are differences between how View elements are displayed in the Design and Blueprint previews. I have a TextView that is centered using the gravity attribute. In the Design preview, in the emulator, and on a device it shows it as centered. However, in the Blueprint preview the same TextView is not centered and sits to the left of its bounding box. See screen shot below.

However, if I add a text alignment attribute of ‘center’ to the TextView then it will show as centered in the Blueprint preview. Why doesn’t the Blueprint preview look identical to the Design preview? And why does adding the text alignment attribute center just the Blueprint preview? Why the discrepancies?