Textbox sizing in word and open xml don't appear to match

Hello, I have a question about the text box positioning and its correlation to the openxml for the textbox.

This template consist of a textbox within a group shape. When I click on the outer group shape and inspect its sizing, we can see that its absolutely sized to about 1/2 inch by 1/2 inch:

When you look at the open xml, the extent is roughly 450,000 emus which is correct:

However, when you inspect the textbox's sizing properties, you will notice its absolutely sized just slightly smaller than the group shape:

When you inspect the open xml for the textbox, it is only about 500 emus for width and height which is drastically smaller than what's defined in the word dialog. There is an attribute in the openxml for the textbox "spAutoFit", however when you edit the textbox in word, you will notice it doesn't automatically size with the text. If you type additional "!" in the textbox, it will begin to wrap around showing that the textbox does indeed have a fixed width.

My question is why is there such a big difference between the openxml and the word dialog for the textbox size?

Here is a link to a folder that contains the docx file along with it's document.xml: https://windwardstudios.box.com/s/9msvsvkic5m68xumubjynird1482744s