1.1 XML Grammar Files reads in part:

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While the files should define the same DITA elements, the RELAX NG grammars are normative if there is a discrepancy. If there is a discrepancy between the written specification (this document) and the RELAX NG
grammars, the written specification takes precedence.
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The last clause of the second sentence conflicts with the OASIS TC Process (7a) (https://www.oasis-open.org/policies-guidelines/tc-process#specQuality):

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For Standards Track Work Products:

*All normative computer language definitions must be provided in separate plain text files;

*Each text file must be referenced from the Work Product; and

*Where any definition in these separate files disagrees with the definition found in the specification, the definition in the separate file prevails.
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The current text of DITA gives precedence to the specification over the separate plain text file.

This is in conflict with the OASIS TC Process requirements.