Note that if Corinth or Decatur are captured by them Yankees...then no RR (Operational Movement) is possible from the main trunk lines of the CSA to Vicksburg or Memphis.
The Battle of Shilo occurred in April 1862 outside Corinth, and you can see why General Grant was so keen to take this strategic town.
Note the RR lines that run north-south in the state of Mississippi. They are linked to the south of this map, but that won't help with sending troops by RR from Virginia for example if Corinth, Decator or the RR line connecting them are severed.
I plan to gather up more interesting strategic peculiarities of this vast conflict area, and compile them in a psuedo atlas in the War Room.
Its a side project that I will add to given time
Cheers