Join works for a single user as well, technically.
However, the problem I see for single-user scenarios is that the write function isn’t partially “localized” the way it is in Pro Tools (I’ll add this as a feature request in the N8 forum).
So the way it works in Pro Tools is that you can first of all set join to automatic and you won’t have to specifically engage it after you press play. It’s similar to the “lock” that shows up in the fill options for example. Anyway, imagine that you have three basic groups of sounds, spoken word (dialog/narration), fx and music. You put those three groups in latch and start writing automation. The spoken word is barely touched because you leveled it before and really all of the rest sits at a lower level.
You get to a point and realize that about 5 seconds ago the fx got too loud. You press stop. You move back 10 seconds and press play again. When you get to that spot IN PRO TOOLS you can simply adjust the fx group, and when you get to the point you stopped playback the music group will go back into automation write again. You don’t have to do anything, it’ll just pick up (join) where it left off.
This might seem like a minor thing but it’s pretty useful if you want to ride levels on several channels using latch and at the same time, and don’t want to have to go back and physically touch the faders again when you’ve started playback again to get them to start writing again.
So this to me seems like an oversight from Steinberg, in my opinion.
Of course it sort of works exactly in the case the manual suggests: If you’re several mixers and someone needs to go back and change something then you can on your computer/workstation choose auto join and just wait until you roll back over the point you stopped earlier.
But for a single user it seems a bit under-developed…
Did that make sense?