What does "Clear Page Status" Actually Do? "No changes to publish" msg when change flag on

Below is the entry from the RW7 Manual on "Clear Page Status. Can someone tell me what this is actually doing? Oh… I know it determines if you have the “change” mark show up or not next to the page, but I see no PRACTICAL result. Changing this setting and having the change mark or not doesn’t seem to impact actual files output next time around (next publish.) ie:, In my case, the change flag may still be on, indicating a page has been changed, but I can still get the “no changes to publish” message… ???

Here is the blurb from the instructions. It really doesn’t say what the RESULT of the option is:

Clear page status when publishing
Whenever RapidWeaver publishes your site, by default the “changed” flag is removed to
let you know that all changes have been published. In RapidWeaver 7, as there is no
“Export”, simply “Publishing to a Local Folder”, the preference to reset this status on
“Export” has been removed.