“You focus on the one thing,” Herbst says. “You don’t focus on the dive anymore. The one thing becomes everything. And I think with Dave it become the body, the body, the body.”

"There was extreme hyperventilation," Cronje says. "On a rebreather at that depth, it would have been very ineffective." Shirley's breathing became so distorted that by the time Shaw faded to just six breaths per minute and then lost consciousness, Shirley was also on the verge of blacking out. His hands were weak and he could barely move. Cronje concluded that Shaw had passed out from carbon dioxide buildup and eventually drowned.

It took Shirley a full half-hour to bring his breathing back under control.

"I actually died with Dave," he says.

NUNO GOMES is the last person alive today who knows what it's like to dive to the bottom of Bushman's Hole, and he understands why Shaw had trouble reacting to a body that was suddenly floating instead of anchored. "You don't think of a new plan while you are down there. It doesn't work. Your mind is clouded. You cannot do it," Gomes says. But he also wonders whether Shaw should have done more buildup dives to increase his tolerance for narcosis—much the way a climber will try to acclimatize to altitude—and his ability to recognize when it reaches dangerous levels. "When he started putting the body in the bag and it didn't work, he should have immediately turned around and left," Gomes says.

Gomes is an open-circuit diver, and his priority is setting records. (In June, he reclaimed the world depth record, reaching 1,044 feet in the Red Sea.) "I didn't think it was worth the risk of a diver losing his life to recover the remains of Deon Dreyer," he says flatly. Even so, Gomes honors Shaw as a fallen comrade. "It was a noble dive, a heroic dive. He did what he believed in, and I've got to say he had a lot of courage," Gomes says. "At the end of the day, he achieved what he wanted to achieve, even though he paid for it with his life."

None of the divers who were with Shaw in Bushman's Hole think the dive was reckless. As support diver Mark Andrews puts it, "If you asked me about the chances before the dive, I'd have said there is a 99 percent chance of success, and a 1 percent chance he'll have to leave the body. And zero percent that Dave wasn't coming back."

Verna van Schaik, who is used to people telling her she is pushing too deep, is sorry Shaw died but not sorry for him. "Dave was going to go back," she says. "The fact that Deon was there just made it more interesting and more exciting. Dave knew the risks. They were his risks, and he took them."

Every diver there that day will keep diving, and instead of second-guessing Shaw, they say they are proud of him. "Dave took rebreather diving where it has never been before. People never knew about [rebreathers] until he died showing what can be done," Peter Herbst says. "Two hundred meters [656 feet] was a damned deep dive on a rebreather. This guy went half as deep again. He made the envelope bigger."