XML for Data Architects: Designing for Reuse and Integration

A key feature of this book is the valuable information defined as:
Facts
Recommendations
Techniques
Opportunities
Facts are based upon available reference or frequent observation. Recommendations are subjective and are the result of my experience and research. Techniques define tactical practices, and opportunities help determine when to apply a technique or avoid a potential pitfall.
In addition to their definition in the chapter text, they are repeated here grouped by topic with page references to supporting context.
Fact: XML is self-describing (supports descriptive element and attribute tags). (p. 12)
Fact: XML is generally interoperable (XML is by default encoded as Unicode and UTF-8, supporting basic ASCII characters). (p. 17)
Fact: XML is reusable (W3C XML Schemas can be engineered as modular component schemas). (p. 19)
Fact: XML is flexible (XML structures can be engineered to dynamically expand or contract). (p. 23)
Fact: XML is extensible (XML structures and schemas can be extended or "added to"). (p. 24)
Recommendation: XML Document Type Definitions (DTD) can be an effective method of describing and constraining simple document-oriented content. However, in many cases W3C XML Schemas can be applied equally well. (p. 33)
Recommendation: W3C XML Schemas are generally a very good fit for transaction-oriented content (both internal and external to the enterprise). (p. 42)
Recommendation: W3C XML Schemas are generally a good fit for message-oriented content. (p. 45)
Fact: Depending upon the characteristics of the data content, the intended use,...