TS&Ms comment regarding the buoyancy control was excellent, I would take it a step further and apply those same principles when on a living reef, whose inhabitants are all alien creatures --surviving in spite of us-- and the footprints of man do not belong.
Don't touch, don't kneel, don't prod with a stick...
I don't think anybody would disagree. However, there's still a huge difference between the cave environment and a coral reef - the coral reef repairs itself (from diver-caused damage, that is) in timespans measured in decades to multiples of human lifetimes; with the cenotes and the speleothems and even ecosystems in them, we're talking about timespans ranging from tens of thousands of year right up to geological time scale. And there's a whole lot of more coral reefs in the world than diveable underwater caves.
While seeing a reef take a beating from inept divers is annoying, seeing the damage in the cenote cavern tour areas (and even some of the more popular main lines) is downright sad. They're still beautiful places, though. They would just be so much better if the speleothems were intact and just about every conceivable surface hadn't taken a hit from a tank, fin or hand.
//LN