Catalogue definition of types (TextType et al)

["David RR Webber \(XML\)" <david@drrw.info>]

I'm noticing that in the Catalogue XSD it defines the TextType et al - but these are already defined in the imports.
 
Is this a mistake?  Should they only be in the imports?
 
The reason is the definition in the Catalogue is circular - and lacks the extended definition in the imports.
 
Just curious.
 
DW
==========================
 <xsd:complexType name="TextType">
                  <xsd:simpleContent>
                     <xsd:extension base="udt:TextType"/>
                  </xsd:simpleContent>
               </xsd:complexType>     
 
as opposed to:
 
<xsd:complexType name="TextType">
                        <xsd:annotation>
                           <xsd:documentation xml:lang="en">
                              <ccts:UniqueID>UDT0000019</ccts:UniqueID>
                              <ccts:CategoryCode>UDT</ccts:CategoryCode>
                              <ccts:DictionaryEntryName>Text. Type</ccts:DictionaryEntryName>
                              <ccts:VersionID>1.0</ccts:VersionID>
                              <ccts:Definition>A character string (i.e. a finite set of characters) generally in the form of words of a language.</ccts:Definition>
                              <ccts:RepresentationTermName>Text</ccts:RepresentationTermName>
                              <ccts:PrimitiveType>string</ccts:PrimitiveType>
                              <xsd:BuiltinType>string</xsd:BuiltinType>
                           </xsd:documentation>
                        </xsd:annotation>
                        <xsd:simpleContent>
                           <xsd:extension base="xsd:string">
                              <xsd:attribute name="languageID" type="xsd:language" use="optional">
                                 <xsd:annotation>
                                    <xsd:documentation xml:lang="en">
                                       <ccts:UniqueID>UDT0000019-SC2</ccts:UniqueID>
                                       <ccts:CategoryCode>SC</ccts:CategoryCode>
                                       <ccts:DictionaryEntryName>Language. Identifier</ccts:DictionaryEntryName>
                                       <ccts:Definition>The identifier of the language used in the content component.</ccts:Definition>
                                       <ccts:ObjectClass>Language</ccts:ObjectClass>
                                       <ccts:PropertyTermName>Identification</ccts:PropertyTermName>
                                       <ccts:RepresentationTermName>Identifier</ccts:RepresentationTermName>
                                       <ccts:PrimitiveType>string</ccts:PrimitiveType>
                                       <xsd:BuiltinType>language</xsd:BuiltinType>
                                    </xsd:documentation>
                                 </xsd:annotation>
                              </xsd:attribute>
                           </xsd:extension>
                        </xsd:simpleContent>
                     </xsd:complexType>