Watched Topics - what does the Save option do?

Hello,

I have set up some watched topics, and I'm finally getting around to asking a question that has been bugging me for a while.

The table that displays the watched topic list has a Save column, and one can choose to enable this option, when submitting updates to the watch list behavior.

While the "Email Updates", and the "Delete" options are fairly intuitive, I can't figure out what the "Save" option is supposed to do.

I looked in the Help file, but couldn't find a clear answer. The only area where the issue of saving watches is discussed reads:
"... you may specify whether you would like to receive email alerts for certain watches, as well as save and delete watches ..."
(see http://forums.emc.com/jive3/help.jspa)

To me, this means that if you enable the Save option, the watch will remain on this list. If that's the case, then what is the difference between that and simply NOT enabling the Delete option prior to submitting your changes?