It's very simple. When you've been trained to be a good buddy and dive as part of a team, doing so is natural and reflects good manners. Do proper planning and pre-dive checks, equipment matching, S-drills, and bubble checks, etc. Mantain awareness of teammates remaining close enough for emergencies, but not too close to crowd and take away the enjoyment for another buddy. When not specifically looking at something allow your light to be in a position to be referenced by others. Periodically scan teammates in detail for anything out of place and check for light cord issues, hose issues, and the like during switches, if a buddy transfers or clips a light, etc. Signal your intentions, mark intersections properly, don't violate rules of accident analysis, etc.
Solo diving is a completely different animal and doesn't confuse the two.
To compare, I've been a lifeguard for 20 years. When I take my place in a tower, I begin to scan the water while being aware of the activities on the sand to prevent accidents before they reach the water as well. I swivel my head back and forth covering a zone looking for different kinds of behavior. I have done this successfully 40 or more hours a week at times for the past 20 years full-time or part-time depending upon whether I was a full-time lifeguard or part-time instructor and vice versa. Yet, the moment that I go to a beach myself, I don't continually scan. I check my surroundings, sit on my surboard, watch for waves, watch for gorgeous women, occasionally check for everyone's safety, but I'm not practicing the same awareness that I would be if on duty.
In a team, I maintain "on duty" type vigilence. Alone, I maintain a different type of awareness, but I check on the status of passing teams. Once, going into Little River before the chimney on a solo dive carrying a buddy bottle, a team of two was exiting with one diver on a backup light. I paused to let the exiting team have the right of way, but asked, "Are you okay?" with my light. I received an "Okay." Had I not, I would have asked if they wanted me to buddy and exit with them. I knew these divers weren't in a class because I knew them. After my dive, this same team told me thanks for checking on us. They had passed others that we knew who practically ran them over with scooters not giving them the right of way to exit and not being aware that the lead diver was on a back up light. You can be even more clueless in a team. I knew the second diver in that team had been trained to be completely aware of environment, team, buddy and self because I trained him in AOW and he suffered far more drills and critique than most of you have had in GUE classes. Their excuse, Yeah, yeah... we didn't care about you guys, we just wanted to wall out the cave and we were on a strict run time." Nice! Goal-oriented dives... always a good time had by all!
JeffG:
Again, that sounds good on paper, but does it work in practice?
Solo diving requires a different type of situational awareness and I can't see how realistically someone could go from "Team mode" to "solo mode".
I'm not saying it is impossible, but I believe it would be improbable.