As noted earlier, metatopics allow you to create higher level topics that can greatly simplify the appearance of a data model.
Unlike other topics, metatopics are independent of actual database tables. You can use metatopics to make the column and join structure of an underlying database transparent. You can substitute instead streamlined and intuitive topics adapted to the way users conceptualize information.
For example, you can replace a data model of joined topics with a single metatopics that contains only the items business personnel need in their queries. The joins are completely transparent.