Like the Northern Line, this was actually attempted once, but it was put into operation first. In fact, the initial run on this line inspired the creation of the Northern Line.
Instead of crossing part of Tennessee and all of Arkansas, why not just keep going south to I-20, and then across the South and into Dallas? By using this routing, you would skip at least some of the Tennessee Hills and the inevitable rainstorms. This is where we learned what the lyrics from “Mississippi” meant – we were in Mississippi a day too long. (Thank you, Mr Bob Dylan.)
The one interesting stop was Chunky, MS. As we passed the city limits sign, it occurred to me that every year in the Miss Mississippi pageant, someone called out “Miss Chunky!” That would not be a desired title, I would think.