Hmmm... Never noticed this before. If you single-click on a list in the library pane, it will show on the current map view the items in that list and will not change the map view. If you double-click on a list, it will show the items but will also change the map view so as to encompass the total items in that list. The single-click could come in handy if you were zoomed in on an area and wanted to see on the map what items were in another list just in that focused area without having to re-zoom/pan back to that area. Double-clicking would be for changing over to work on a different list.
Another undocumented feature, or maybe I missed finding it... I wonder if the writers of the "help" have ever actually used BC? Something like this would commonly be found in most software documentation as a "tip".
