You may find interesting the following report by Howard W. Pollock entitled:
A CLASSIC CASE OF DIVER AIR EMBOLISM AT THE SURFACE FROM HIGH WAVE ACTION
http://archive.rubicon-foundation.org/6120
According to the article:
1. "The accident occurred following a 3 day saturation dive..."
2. "a normal ascent, at least until the dive team was about 15' to 18' from the turbulent surface..."
3. "10' to 12' waves were breaking against structures and equipment on the surface..."
4. "He was then towed on his back by two support divers, unisuit inflated, regulator in his mouth, with his head out of the water. Although he was virtually incapacitated on the return to the support vessel, there was an occasion when some of the seas washed over causing Joe's mouthpiece (regulator) to come out, and he personally replaced it with his right hand and held it in place momentarily: but, then both hand and mouthpiece fell away. One rescue diver later commented, 'his eyes were open, although I can't recall seeing him blink as the water passed across his face.' Another diver reported that when Joe was being towed a white frothy foam was bubbling from his mouth."
Point 1 tells me that this guy had been under other than usual conditions that we normally would associate with recreational divers just prior to the embolism. Even though he may have been put through the decompression protocols that were considered applicable in the mid-seventies, saturation diving separates this case dramatically from the normal conditions expected with dives done by recreational divers. I wonder if the embolism didn't have more to do with his saturation activities during the prior three days and perhaps even with the irregular ascent during the last couple of feet to the surface than with the fact that he had his reg in his mouth at the surface when he embolized.
Points 2 and 3 seem to imply that the ascent rate followed by the dive team during the last 18' to 15' was not normal and most likely accelerated and even made worse by the 10' to 12' waves breaking at the surface. I have personally experienced what it feels like to do a fun roller coaster ride at the surface with 8' to 10' swells; thinking about 10' 12'
breaking waves though must have been
seriously daunting. These are not conditions that I think your average vacation diver will most likely ever encounter when they sign up for the morning dive roster at Popeye's Dive charter.
Finally, point 4 seems to describe the events at the time the embolism occurred. The diver was being towed by the support divers at the surface with his unisuit fully inflated and his head out of the water. He even replaced his regulator himself when it was washed out of his mouth by some water. This makes me think that he was conscious enough at the time and since one support diver mentioned that he could see Joe's open eyes but could not recall if he saw him blink as the water washed over his face it leads me to think they were not in a Maytag spin cycle when Joe embolized but that the waters were rough enough to wash aggresively over his face.
In this case it does not seem as if Joe held his breath and resurfaced from a depth that could have caused lung over-expansion injury or anything similar that could have caused him to embolize. It seems more likely to me that he may have embolized due to sudden reduction of ambient pressure as they surfaced the final 15' to 18' to the surface which was probably made worse by the huge breaking waves. Having just completed a saturation dive just prior to the event doesn't help either. Without more information I suspect that these were extraordinary circumstances that most recreational divers would never see so I see very little that suggests that anything in this article applies to the OP's thread here.