So there is no responsible person? How can you just ignore the fact that someone does not show up? You cannot assume the missing person will use In Reach for help. He may have fallen and hit his head and is unconscious. To me that is not a group at all.

When I lead a group, we by no means are right on top of each other. If we cannot see the person behind us, we stop and wait, but we can be relatively spread out.

I do a lot of off-trail travel, which is an entirely different thing. The advantage of staying in a group is to share the route-finding. The first person does the gross navigation, focusing on staying in line with the intended target; the second person is what we call the "smoother-outer" and he stays with sight, but far enough behind to find the best micro-route, detouring difficult obstacles, or if the leader zig zags, he shaves off the corners. Third person basically follows but can also add route refinement. The last is the "sweep" making sure nobody is left behind. When traveling in snow (early season), breaking trail is tough work, so everyone trades off. The group as a whole can actually go faster than a single person doing all the work.

I suppose this will become a lost art, as everyone simply looks down at their GPS and follows the arrow.

If you do not plan to stick together, be sure each person has sufficient gear and food to spend the night out. If one has the tent and one the poles, the tent is not going to do anyone any good.

The only time I actually travel alone and meet up to camp is when we both are TOTALLY independent in gear. Still is a problem if I get to my car and the other person does not and is riding with me. I do not do this very often.

Both having an In-Reach with the ability to communicate with each other would be a big help.