The only way to remove the "You are Here" line is to remove it from the underlying skin controls.  It is a pretty straight forward change.  Using a text edtior like notepad, open one of the layouts you would like to use (these files are located in your /portals/_defaults/skins/darkknight folder).  Find and removed the line that starts with:

Now save the file with a new name so you have a version with and without the breadcrumb bar.