This is just an idea/suggestion based on my understand of the problem with refactoring. Ideally it would be nice to have a list of changes that development does but in reality this does not really happen. Though not a perfect solution would it make sense to do the following after the WSDL has changed.
1. user updates the definition.
2. user selects to force new method definition to all instances of that method across all test cases in the project.
This can drastically change the project and will likely cause many property transfer failures. However, I think those are easy to fix/rescript. I would personally first create a backup of my project before doing this since its such a big change in the project file.
This approach fixes the major headache that I (QA) have - I am issuing request to my web service using XML request structure that is no longer supported because the WSDL has changed.