Alexander Deliyannis 10/12/2013 6:11 am
Stephen Zeoli wrote:
There was an two-pane outliner many years
ago that could do this. The name escapes me and it is long dead,
unfortunately.

You refer to Acute Notes http://www.outlinersoftware.com/archives/viewt/2365

The program has not been developed since 2002 and the website is gone, though you can still be download the file from the like of http://download.cnet.com/AcuteNotes/3000-2074_4-10129515.html

Jim, see my post above for a contemporary solution to this as provided by SENSE, though I know it's not everyone's cup of tea.