If a performer changes to using a nickname, say from Robert Johnson to Bobby Johnson, should they be listed separately?

If a band keeps the same personnel, music, etc. and changes only its name? What if they change one person, and the name change is for intellectual property reasons (e.g., the departed person owns rights to the original name)? What if they also were an acoustic folk band and plug in, switching to rock? To jazz? What if everything changes - personnel, music, etc. - except for the name? What if they retroactively rename the band or music for intellectual property reasons?

... as with every attempt to specify reality.