Condition of Cozumel Reefs

I recently dove Santa Rosa Wall and Las Palmas in Cozumel. I was very
surprised at the condition of the reef. We were between 50 - 80 feet
on Santa Rosa, and much of the reef was covered with sand. There was
a strong current at Las Palmas, so I'm not sure if the dive master
kept us on the reef or not, but we basically saw small islands of
coral and lots of sand. I had heard that the reefs were fine below
fifty feet or so. Did I pick two poor sites, or are these sites
fairly typical of Cozumel following Wilma?

Edward