A recent thread on the dita-users list discussed specialization as an extension of the DITA OT by restrictive substitution. This is best done by creating a DITA-OT plugin.

Plugins are overrides to the OT code that add functionality. Plugins are used to add new specializations to the OT and to define new specialization targets for output processing of the specialized elements. If they are designed properly, plugins can be added to an upgraded version of the OT and still run properly.

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The Central Texas DUG presentations on Wikis and DITA, and Eric Arnstrong's excellent review of the benefits of structured formats and DITA compared to alternatives like a Wiki, raises the question of whether we are perhaps trying to force DITA into too many places.

Eric focused in on the reason structured formats are difficult to use -  they force you to learn the tagging structure (DITA has about 120 tags, DocBook 800, and XHTML only about 80).

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