While reading through the thread on recalculating thirds, the topic of recalculating thirds on the Grand Traverse at Peacock came up, specifically on the fact that there are multiple exits. I've been meaning to have a discussion on this topic, but have been hesitant to as I think it's slightly controversial and I don't want to get flamed. For clarity, I have not yet done the traverse, because there's been lots of other dives in Peacock I'd prefer to do.

So during my training, I had different instructors for Cavern/Cave1 and Cave 2. Both instructors used the Grand Traverse as examples for teaching advanced navigation and to push the idea of learning the cave before making advanced dives. Both instructors had the same opinion on the Grand Traverse, and their way of explaining it is obviously taking the most cautious approach to a long traverse.

To take anything superfluous out of the equation, let's just say we want to do the traverse from Orange Grove to P1. That means along the way our POTENTIAL options for emergency exit would be Challenge, Olsen, and Pothole(which I know is no longer an option), other than turning back to Orange Grove or pushing forward to P1. I was taught by both instructors the appropriate way to perform the traverse would be the same as learning a new circuit. You would start by doing several dives as learning the cave dives. Starting from OG and diving to 1/3s (or whatever gas plan you choose), you would mark the line or notate your turn point in your wet notes. You would then do a dive from P1 towards OG and noting if you made it to your previously notated turn point. Both instructors recommended doing these dives several times to prove consistency. Once you have proven that you can get to the "mid-point" repeatedly and easily using your gas management plan, then you can attempt the traverse. While doing the traverse if you don't hit your mid-point, you turn and head back to your entrance.

In discussions in both classes, it was agreed that while Challenge and Olsen could be used to climb out in an emergency, why take that risk. I'm sure I could climb out of Olsen, but Challenge doesn't look fun unless you're leaving all of your gear behind. Obviously doing the traverse in this manner is the most cautious approach.

Now the kicker. Since being given my ticket to learn, the more people I hear discussing the traverse, the more I hear it being done completely differently. The way I very commonly hear people discussing is that they would dive from OG to Challenge. Once at Challenge they would recalculate thirds. With this new recalculation, if they didn't hit Olsen by the time they hit thirds they would turn around, using Challenge as a potential emergency exit. If they did make it to Olsen, they would then recalculate thirds again for the rest of the trip. Where some differed is that with some the new recalculation would be planned to get them to Pothole, and others it would be to P1. If they didn't hit their new mark before thirds, they would have to make a turn decision.

Compared to how I was taught, this alternative choice seems frought with risks. I do realize many people can do the traverse without a stage or know from experience that they can hit the midway mark and therefore just finish the traverse. The majority of people that told me they did the traverse based on this second method of travel were using this gas planning of recalculating thirds on their first attempt at the traverse. When I've explained that's very different than the conservative way I was taught the responses have usually been either "that's how people who have done the traverse taught me" or "well that's how everybody does it, so it's fine."

I tend to be ultraconservative, so to me the recalculating thirds is not my cup of tea and something I wouldn't do. There also seems to be a little bit of pride in discussion I've had with people that carrying a stage to do the traverse is not necessary even if it's just meant as a safety.

So what seems to be the norm? Is what I was taught in my courses what most people are really doing, and my discussion with people that do the recalculation isn't typical? Is part of your plan for emergency to climb out of challenge or olsen really a smart one? I've often wondered if the people who do include a climb out as part of their emergency planning taking into account that it's possible the emergency is an incapacitated diver? How would they get you or your buddy out of Challenge if he/she had a heart attack and can't climb out under their own power.

My intention is not to say that people who recalculate are wrong. And I know my conservative mindset isn't the norm. These are just questions I haven't really been able to understand and I've pondered since the first time I was told of the recalculation method of doing the traverse. Hopefully my long stream of consciousness post isn't too rambling.