Save All (File > Save All, Opt-Cmd-S) should not save unchanged files. I’ve found two workflows so far to which this is really disruptive:
I have a bunch of files open. Some of these files are being watched for LiveReload. I edit a handful of other ones, Save All, and LiveReload gets triggered unnecessarily.
The Tidy Tabs package becomes useless, because when I use Save All, all of my tabs get marked as having been recently saved.