Good to see this in preview; hope it stays.
The Amtrak line and the Metro Electric line in Chicago are two separate lines (Amtrak uses the 2+ freight tracks to the east). Connections between the two sets of tracks, if any, are extremely limited; the electric tracks simply dead-end after University Park.
The line south of Memphis (just north of the state line) should probably be midway between the two rights-of-way. The 2007 CN timetable shows it as a normal two-track line, and I don't see any special conditions listed.
The line in northeastern Charlotte should be separated from NC BluLn; the two have separate tracks with no connections and no shared stations.
More to come, maybe.