When I use 'Search for Items' and add the sprint column, may items are shown as being in sprint 'None +1'. What in the Heisensprint! Surely it's either in no sprints, or in 1 sprint?
As far as I can tell, this happens when the sprint an item was completed in is closed but for some reason it doesn't want to show the sprint name in the list.
This is doubly frustrating as I was trying to use this view to view work items in completed sprints so I can tag them with releases as I haven't found another way to view closed sprints but that's probably best kept for a separate question!