ITS rules mapping for ITS namespace

There is a set of ITS mapping rules in
http://docs.oasis-open.org/xliff/xliff-core/v2.1/csprd02/schemas/its.sch (in
5.9.2 Module
Namespace and Validation Artifacts).

It seems to contain mapping for data categories that are represented using the
normal ITS namespace. For example there is:

<!-- Rules for Localization Quality Issue. Note that the pointer
attribute is only available for the local
locQualityIssuesRef attribute, hence the mapping is also only for that attribute
and no other Localization Quality Issue attributes.
But this limitation is OK since a processor can work with this data category
locally.-->
<its:locQualityIssueRule selector="//xlf:mrk[@type='its:generic' and
(@its:locQualityIssueType)]"
locQualityIssuesRefPointer="@its:locQualityIssuesRefPointer"/>

There are other instances of this.

Do we need those mappings? If it's in the ITS namespace, an ITS processor should
just be able to process the <mrk> no?
Am I missing something?