To get the word "Author" document property you would normally enter Ctrl+F9 and type "DOCPROPERTY Author".
{ DOCPROPERTY Author }
In the particular instance I am dealing with, the code has been entered
{ AUTHOR "Frank Miller" }
The difference in behaviour (both 2007 and 2010) is that when edit the Author property then right click and choose "Update Field" on the first instance, the display is changed to the new Author. In the second, the document property is instead changed to "Frank Miller".
Is assume this a designed feature, if so is there any documentation on this? What is going on here?