What do you think would happen if say, CSX and UP would merge? Would the line then be viable? I'm refering to the B&O from Cincy to St. Louis. I remember at one time many years ago CSX did think of directional running. Say westbounds via Louisville and eastbounds over the B&O to Cincy. I think it still would be a mistake to abandon any remaining parts of the B&O. In the age of capacity issues I think it's use has not come to an end, but I know the inevitable most probably will happen. Like you said though, all of this may change tomorrow. There was some local "rumor" of NS getting the CSX line from Cincy to St. Louis as part of the split of Conrail. I wonder if NS could of used it for trains that run south to Danville then east to Louisville and onto St. Louis. I don't know what trains use that routing then or now. I was hoping the "rumors" were true because I knew the B&O would get the boot if they weren't.
I'd love to see it - but most of UP's traffic from the west runs via Chicago - again, UP won't run anything into STL that doesn't have to due to costs and congestion.
As far as traffic coming up from Texas and Louisiana- traffic for points south of Cincinnati would run into Nashville, which is CSX's loose-car focal point for the south. Traffic going east already goes into Avon yard for classification. If CSX/UP were to run the traffic into an already-stressed Queesgate yard, east coast traffic then has to run up to Sidney and pick up the STL-CLE main line, which adds a couple hundred miles to the straight-in routing via Indy. No gain there. Again - fine for overflow traffic and a little bit of traffic to flesh out freights bringing in cars for Cincy-Dayton local customers. but it's not the way CSX/UP would want to handle it long-term.
While traffic from UP sources routing over CSX lines would increase, much of the increase would balanced by the loss of traffic coming off the BNSF, which would certainly have to merge with NS.
Sadly, the Indiana Division's fate was more or less cast when the B&O main from Cincinnati to Grafton was abandoned - it's an east-west main with no eastern connection.
It's sad to watch - my grandfather, who lived near Brownstown, IN (between Seymour and Mitchell) and later North Vernon, IN, was an RPO clerk who ran the "Cin and Saint" over this line for 20-odd years. I spent many, many hours shagging up and down US 50 in pursuit of B&O freights. I also had the pleasure of riding the "George Washington" connection from Seymour to Cincinnati for my first real passenger train a couple of year before Amtrak.
Eventually, I think Mitchell-Aurora will share the same fate as the mainline in Southeastern Ohio, near where I live today - a few patches of track in place here and there, but mostly a gravel path.