The original intent was to have the ability to create “inlined” components and fields within messages and components (known as message elements in the repository). The standard uses componentRef and fieldRef right now. The vision was implementors could inline <component/> and <field/> where needed. Unfortunately the current production schemas for the repository 2010 are deficient and do not contain this ability. Several Itiviti customers and some major players, such as Bloomberg and CME are reliant on this feature.
I think this is a reasonable approach that should not impact existing users, while giving the main adopters the feature they rely on.
We should probably make sure 2016 supports inlined components as well.