I worked on the .NET developer team. My executive want to know about the benefits of using Modeling Tool such as MS Visio or Ratinal XDE to develop and design UML Modeling (Use Case Diagram, Sequence Diagram, etc.). Now we're designing the application with DFD and ER Diagram.

Chapter 1 has a section called "Why use UML?" and one called "UML Modeling Tools", which together state the case.

I hope that helps,

Tony Loton (Author)
http://www.lotontech.com