When I was watching it, I commented to my wife that he must have balls of steel to swim through a wreck that way. While there is the fact that he could see straight through the wreck, all I've heard and read about wreck penetration is that there are so many chaotic elements that you can't calculate - parts breaking loose from rust and falling, sea creatures, snags, silt, etc. A freediver has the benefit of the ultimate streamlined shape for a human diver, but at the cost of time to deal with problems from having a supply of air right on your back.
Of course, freedivers are a rather different sort anyway.
