Question for Cozumel Surge/Invasion veterans ....
Other than as a margin increaser/feel better tool is Nitrox at all necessary for the group profiles that we are going to be diving?
I've got my Nitrox card, but not sure if the cost/hassle (of switching gasses between boat (Nitrox) and shallow shore dives (air), etc.) is worth it. I did Blackbeard's in February, and while air vs. Nitrox shortened the deepest parts of the profile a bit on some dives, I can't really say that I was missing out by shallowing up a bit. Even with multiple dives a day, my loading was staying down. My limited diving in Cozumel in 2018 also doesn't make me think that there will be great time while deep.