This is one of the tools that once you get a good grab of it, you can’t let go…
For me it’s invaluable the information it gives me to debug my custom soap headers or my JSON streams.
One trick though, if you are hosting your services on a webserver on your own development box, use the machine name instead of localhost on your HTTP requests or Fiddler won’t intercept them.
Other than that the TextView/XML View is the perfect tool to see what you’re sending on your SOAP request:
Happy SOAP envelop debugging 😉