Not for streaming media. Some people believe that clearing those will get you past throttling but others claim that isn't so. I've yet to see a performance change modifying DSS so I personally leave that one alone. That's the Device Self Service proxy, used for activation and updates. You can see from the name alone why I didn't go there.
I was able to make all the setting changes, but JPEGs are still reprocessed. Can anyone confirm that this still works for them?