When a message list shows a view that is threaded, is it possible to remove the title/header line at the top?  In my case, the view is threaded by subject, so the common message subject appears at the top of each group.  Ideally, I'd like to have the threaded view appear as it did in early versions, where there was a "+" to the left of the first message that could expand the view.  I don't see the need to use the screen real estate to show the subject, which also appears in each message's line.