Relational DB and Everyday Users

Unfortunately, the mathematics of relations escapes most everyday users of databases, and the quest for ease-of-use amounts to little more than a tradeoff between representational power and simplicity. For example, relational systems for everyday users rarely allow true relational joins, and many can only use a single table at a time, even though the representational utility of the model fundamentally relies on ability to decompose relations into multiple "normalized" relations. 

http://www.freepatentsonline.com/5283894.html

Reminds one of the SharePoint "phenomenon"