The method for extending specialization-aware transforms is described in more detail in the document, Specializing topic types in DITA.

Yes. Many writers have had at least some experience with HTML as a markup language. The base DITA declarations (DTD and XML Schema) incorporate a number of familiar, general HTML element names. Through specialization, these can always be extended into more specific forms. Generally, XSLT-based transformations from well-formed XHTML into DITA provides faster and more reliable migrations from HTML than copy/paste, although a skilled writer might be able to do so for small portions of content.

Specialization is the process of creating new categories of topics, or information types, as well as new categories of elements, or domain types. You can define these new types using the existing ones as a base. For example, a product group might identify three main types of reference topic - messages, utilities, and APIs - and define three domains - networking, programming, and databases.

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With information types, you can divide topics into categories that you can manage and keep consistent more easily than without information types. Information types also make it easier for users to find the information that they are looking for: how-to information in a task versus background information in a concept versus detailed specifications in a reference topic.

An information type describes a category of topics, such as concepts, tasks, or reference. Typically, different information types support different kinds of content. For example, a task typically has a set of steps, whereas a reference topic has a set of customary sections, such as syntax, properties, and usage.