This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
You are right that in this particular case a single element could be enough.
However it is a known convention to have a common root to all inner elements. So even though with one element it is not really helpful, it is still used. It also makes the SOAP more readable as the wrapper element name is based on the method name.
Web Services Performance, Interoperability And Testing Blog
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link: http://aspose.com
subject: Complex Type versus Simple Type in a WSDL definition