I haven't been able to find it or emulate it. It would be great but each user is sharing the same instance of Vim and sharing their shell (well, in Pairing mode, at least).
I was just thinking of its rogue mode. I remember each person having their own cursor and being able to work independently in the same session with it.
Maybe I'm thinking too much in the context of pair programming. When I share a workstation with a person there's one cursor there, but perhaps this is a different goal.
... I forget people use vim to do anything but programming?
when pair programming in person you can trivially point to a bit of code with your hand, if you just share a tmux session (or screenshare via Skype/hangouts) you can't do that and it becomes a bit awkward.
Multiple cursors allow you to do this ("<hover> this bit of code" vs "the second condition on line 60, around column 40?" more naturally.
Switching control ("we can do it this way, let me show you") also has less friction with collaborative editing tools compared to classic in person pair programming (no need to shuttle a keyboard/chair back and forth).
When I started using Screenhero which allows screen sharing with multiple cursors it was incredible how effective it felt.