I would first like to point out that the OP got a lot of advice on this dive from people who made presumptions about the conditions. For example,
Ok, if I do that dive I want to follow someone who knows how to frog kick
Good advice in a silty cave, but look at the video. The diver in front of the camera was hand sculling and scissor kicking (with floppy Volos no less) the whole way and it did not do squat to the visibility. That is because all the Cozumel swim throughs have course sand bottoms that are momentarily stirred and then settle immediately.
Mike your video looked pretty good minus the lack of available light. But what we really want to hear is what your plan for the dive was. You knew you had this dive coming up, did you figure out how much air it would take to surface safely between two divers on one tank and what your turn pressures were? If you can say yes, I think across the board you'll earn some respect for a good planned dive and diving the plan.
That is one way to plan a dive. If you look at the end of the video, you will see that the DM is checking the first diver's air supply. The turn pressures were explained on the boat before the dive. (I know the operator, and I did this dive with them last week myself.) It is a multilevel dive, and the DM will plan the ascent based on the pressure and NDL of the most compromised diver. Of course, the wise diver will be ready to overrule the DM if necessary, but a planned multi-level ascent of this nature is a safe plan.
With that stated for the record... there is no good reason to go to 130 ft on any dive unless there is something specific you're going down there for.
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But again... unless you have a really good reason for going down there - why bother?
Most life on the reefs is always between 20-ft - 60ft.
I think the structures there show a very good reason to go there. Reef life is not what you are looking for on this dive.
I would say that if you dive to 130 FSW you will get narced. How much depends on the person and on the day and the dive. Narcosis can be a much more variable thing than one would think.
I agree that just because you are narced, doesn't mean it will be a death struggle. But it does mean that your mind will, at least to some extent (and that varies), operate less well than it does at 30 FSW.
Yes, there will be narcosis, but it is not the kind of thing where people go into stark raving lunacy. Spending about 3 minutes under 100 feet without doing anything more difficult than following the diver in front of you will generally not put anyone into any kind of narcosis situation that will cause harm.
BTW, the group I was with was totally ecstatic about the dive when they were done. I was the only one who had ever done the dive before, and they all decided it was the highlight of the week--except maybe for what they did the day before (Punta Sur Cathedral, a similar dive.)
I think people should make sure they really know the site before issuing their dire warnings.
