I've seen this model used before. It's basically the best thing for teaching unix as far as I can tell - show don't tell and all that.
Now, you're bashing screen a lot in this post - ignoring the fact that screen has a "multiuser mode" which is pretty easy to activate, and does exactly the same thing. I find it comes up less that I want to attach multiple windows to a terminal.
Personally I use this script to GET AROUND that very feature:

NUM=`tmux list-sessions|grep -v \(attached\)|head -n 1|cut -b 1`

if [ -e "$NUM" ]; then

        tmux attach-session -t $NUM

else

        tmux

fi

(yes, I know, it fails if I have more than nine attached tmux sessions as my first nine).
However - tmux is GREAT for certain tasks, and likely better than screen. But never accuse gnu of not having enough features, they'll put it in.
Somebody claiming to be frantisek holop wrote:

quoted text
> good day,

>

> one of the most striking visible differences between screen and

> tmux (as opposed to their architecture, code quality, etc) is the

> philosophy behind attaching clients to an already existing server

> process.

>

> screen was "exclusivistic", latest client wins kind of guy, while

> tmux is exercising a there is enough for everybody where this came

> from world view.

>

> as an old time screen user i was perplexed to see that when i

> attached to an already attached tmux session, both clients were

> updated real time and accepted input as well.  the ascii art with

> the differing terminal window sizes is also a breakthrough idea.

>

> so when a friend of mine asked me to coach him "unix administration"

> remotely, i knew instantly that tmux will be infinitely useful for

> this.  not just a poor man's vnc or remote desktop or whatever,

> but the ultimate terminal experience being thaught through that

> very same tool that is actually the most important for remote

> adminstration.

>

> i created a tmux user, told him to fire up putty.  we logged in

> both as the tmux user, he attached to my session, and voila, the

> ultimate interactive learning tool.  he was floored from moment

> one about the dark powers of the terminal :]

>

> now if only the mouse could be intercepted so it could be used as

> a highligting/pointing tool, a lot of copy mode running around

> could be saved, but that would be really just the topping on the

> cake.

>

> look me up when you are in prague Nicholas, you are my guest.

>

> -f

> --

> strength of mind: person who can eat one salted peanut.