I'm not quite clear on a couple of things:
- At the time you chose to continue the dive, did you know what the issue was with your buddy who was sitting on the surface?
- When you chose to continue the dive, was it clear who your new buddy was?
The reason I ask the second question is that it can be difficult to communicate underwater that you want to join another buddy pair (to make a 3-person team).
No, I didn't know what his issue was until the dive was over and I got back on the boat. But I was certain he was ok because he never showed any signs of a person who wasn't ok. He was just bobbing along up there.
Before the dive, they may have told us, this being a drift dive, that the boat would follow the bubbles and if we came up early they would be there to pick us up. It's been so long ago that I don't remember the dive brief, but somehow I knew (or maybe was just sure) that the boat would pick him up.
After returning to the group, I didn't try to buddy up with anybody. In fact, I stayed at the back since the DM was in the front. Frankly, I was a little concerned that the DM would notice my buddy was no longer with us and I'd be on the hot seat for leaving him, so I was trying to avoid him. I'm pretty sure he never noticed, at least until we ascended and maybe not even then. I wasn't going to bring it up and he never did.
Also, it wasn't like the group was swimming in buddy pairs. It was more like one big buddy group. I remember being surprised by that at the time, although I've since seen plenty of buddy "pairs" that are really just buddy groups.
That is a tuff call for any diver new or not. You could have probably surfaced got a clear answer to what the problem was and still rejoined the group. However...
What would have been your contingency if you lost your group on the way back down, now your alone and probably dont have any surface siganling devices should you need to resurface... not looking for an answer. but wanted to point out to others reading this thread that you must have a contingency and think before you just act on something.
It seems you did and make a conscious decision, was it right? only you can really decide.
An issue here is the DM, every location takes this responsiblity a little different. But I was always tought to be the last one down to help those that have problems with weighting and getting down for other reasons. You can't help them from underwater. Since it seems he got down initially, but displayed weighting problems, i would think the DM would swim over and donate a weight to help him out. Most DM's I know always carry a few extra pounds for such cases.
Well, I wasn't going to lose the group since I could still see them, barely, when I left my buddy and chased after them. It was a fairly stiff current so there's only one way for them and me to go and I was on them quickly. Had I lost them, though, I would have surfaced and gotten on the boat, somewhat sheepishly.
I didn't have a SMB but didn't think I needed one. My memory, always a little suspect, is that there were dive op boats all over that water so the concern was more about not getting run over and finding the right dive boat, not losing it. But diving in Coz is way different than diving alone on an open ocean. And again, I don't remember if they briefed us but somehow I was confident that the boat was following our bubbles. Given that it was my first boat/drift dive, I don't know how else I would have known that if they hadn't told us so before the dive. And I'm not sure why I didn't think about surfacing to determine his problem and making sure the boat was coming to pick him up. Chalk that one up to inexperience.
Looking back, I did a bunch of things wrong or at least not as well as I would do today. Not big life-threatening things, just little things. I'm absolutely convinced that leaving him at the surface was the right thing to do
under those circumstances. But it wouldn't take much in the way of changed circumstances for it to become the wrong thing to do.