[The Soup Nazi]

Originally Posted by Skuj

If you are an old fashioned CD person like me, why the fuck is this going to be a 2CD set?

From Under The Radar:

Bob Dylan has announced a new album, Rough and Rowdy Ways, and shared another single from it, "False Prophet." [...]

Dylan dropped two other introductory singles off the album: the lead-off track "I Contain Multitudes" and the 16-minute, 55-second "Murder Most Foul." The latter became Dylan's first song to hit No. 1 on the Billboard chart, a song so vast that it has claimed its own separate disc in the CD album package. "Murder Most Foul" was one of our Songs of the Week.

So there you go - the "vastness" is the reason.