Say you have the following:
- Planet List
- Country List
- Region List
- Town List
- Street List
Street List has a content type called "Street", which in it has a lookup to the Town List. So the flow for creating a new street is as follows:
- Create a planet.
- Create a country, specify planet in dropdown.
- Create a region, specify country in dropdown.
- Create town, specify region in dropdown.
- Create street, specify town in dropdown.
Each list has it's own specific properties (Planet has "SE Co-ordinates", Country has "Main language", etc..). This means that these cannot be used as managed metadata tags.
Now, I'm going to create a new document in the document library which has a content type using the "Street lookup" field.
Obviously, in the document information panel in Word - I'm going to get a gazilion different streets to choose from (including ones from other planets :P).
You can always hack your way around it in the UI. But this seems like really basic functionality - am I the first one to add addresses to documents in SharePoint??