The DITA 1.3 language specification "B.3 File naming conventions" states that:
Document type shells should be given a name that distinguishes their name, owner, or purpose; for example, acme-concept.dtd. The document type shells that are provided by the DITA Technical Committee use the root element of the primary specialization as the basis for the file name.
The draft DITA 2.0 language specification "Coding practices for DITA grammar files" also states that:
Document-type shells should be given a name that distinguishes their name, owner, or purpose, for example, acme-concept.dtd. The document-type shells that are provided by the DITA Technical Committee typically use the root element of the primary specialization as the basis for the file name. If necessary, a qualifier such as base is prepended to the name of the root element.
So the original approach was correct and this should be reverted for clarity.
The DITA 1.3 language specification "B.3 File naming conventions" states that:
The draft DITA 2.0 language specification "Coding practices for DITA grammar files" also states that:
So the original approach was correct and this should be reverted for clarity.