Do you think they are doing this efficiently??
Cmon its been five year plus and we still dont have anything. This is less than 200 feet, not even a football field. Many big buildings have parking garages down more than 200 feet. It doesnt take 5 years to build the foundation for a skyscraper. Open pit miners could dig a hole 20 yds X 20 yrds and 200 feet deep in a few months. I think these guys have already found thier treasure in the form of selling episodes for five years and as long as they can string along a crowd this could take another five. There are also ground penetrating radar and underwater probes which could be used but that might end this sooner than they would like.
I do. There are many areas to explore. I wish they would take the first advice of the designers of the booby traps and fill the elaborate waterways (the ones where the parchment paper, gold chain link [which was a form of money in early days]) with corn to block and clog the water from entering. The historical engineers gave this information for others from their voyage to stop the water to allow exploration and re-entering.