ahh, sorry I didn't know if there was something in the middle of the thread.
So to answer
@DBPacific
I went solo very early in my diving because I was at a university and we were teaching. Teaching=solo, always. Whether that is as an instructor, or for us in the beginning, NAUI training assistants, you are diving solo. For me that was my second semester of diving.
I don't have any solo certifications formally but we train all of our divers from day 1 to be fully self sufficient with what they have. That does not include redundancy because we emphasize the importance of buddy diving in the beginning, but they are trained to make ascents properly when left solo in a lost buddy situation, how to remedy situations etc.
Within the confines of AAUS, there is a STRICT requirement for the buddy system, defined as the following "a diver is accompanied by and is in continuous contact with another diver in the water."
In post 1 you are describing same ocean diving which is how I normally dive with my buddies, but that does not follow the definition above and would be in violation of standards.
Now, buddy diving in the AAUS standards does not necessarily mean that you are relying on each other as is the case with most definitions of the buddy system, and when I'm doing scientific dives, my buddy and I are usually wearing doubles or a rebreather and are completely self sufficient. This is more in line with the DIR/GUE/technical diving definition of a buddy where you are each a member of a team in order to make whatever task at hand easier. Scientific diving is all working dives so in our opinion you have to be fully self sufficient and your buddy is only there to assist in the job at hand.
On your lobster transects that can be a little dicey if you don't have FFM's and comms. Note that the rule says in continuous contact, that can be verbal through the use of FFM's if you are diving in areas where touch/visual contact is impractical as would be your case there. In that instance you know generally where your buddy is, are in visual contact with the transect, and as long as it is made clear that the team arrives at a transect, dive leader stays at point or side A, and diver 2 moves to the opposite, or one of the adjacent corners or sides *usually opposite*, then that's very different.
Unfortunately I do know that our divers are trained to an infinitely higher standard than the vast majority of programs so the types of things we can have our scientific divers do is very different than most. We will often have previously certified scientific divers come into our program and fail our scientific diving course the first time around and be sent back to basic training again so they can learn to dive in flat trim, with good buoyancy and propulsion, and proper buddy contact. Only when they can demonstrate competency at that basic navigation will they be allowed to start doing working diver training.
