Oh, that's not quite what I meant. The question wasn't about whether I should use {screen,tmux} to open a shell; the question was whether I should use {tmux,etc

Oh, that's not quite what I meant. The question wasn't about whether I should use {screen,tmux} to open a shell; the question was whether I should use {tmux,etc.} to manage multiple shells in the same terminal window. As opposed to having multiple instances of them open in different windows.