Archive a Mailing

If I archive a mailing can I still see the metrics on it?

The archiving functionality is an additional section in Email Playground to help with organization (de-cluter your "My Saved Emails").  

If you go to the "Archived Mailings" section and scroll right of your mailing, you'll see the briefcase to move it back, as well as the table icon to see the metrics exactly as you would in the My Saved Emails section.