My initial attraction to screen / tmux was when I spent most of my time logged into remote servers. The ability to start a long-running script at the office, detach from screen, then re-attach at home to check on it later was indispensable.

Can you do this with traditional commands? Disown detatches from the terminal (if I remember correctly), is there an equivalent to re-atach it later?

With tmux you can have multiple terminal panes going in a session, disconnect, and then reconnect.

Even better: use iTerm's tmux integration!

In my current workflow, I ssh into a server and then run "tmux -CCu attach -t main", which will open all the windows and tabs that I had open previously, but as regular iTerm windows and tabs. It's possible to also maintain tab/window colors and such, but I found all that to be a bit fiddly.