I'm part of a project developing an application for states to use when managing various programs. As such, we have to provide a data dictionary as part of the deliverables, but some of the descriptions the developers supplied are things like "this is the ID field" or "disscribs the person" [sic]...Not helpful and not accurate, and shows that, sometimes, developers aren't the best at using English! I created an Excel/VBA tool to pull the table names from the database, create a tab for each table and populate the new worksheet with table and field names, and also the extended properties for each. At each milestone in the project, we deliver the Excel file to the documentation department for "wordsmithing", then another button on the Excel file updates (or inserts) the MS_Description property in the master database. Quick, easy, adapts to changes in the tables, and allows the developers to concentrate on writing code, while the documentation folk get to do what they get paid for.
The only hiccup in your detection of blank extended attributes is when the developer uses "Must populate this" as their description for each and every field in the tables they create! :-)