This one comes from Helen on YD. It's her theory about the cause behind unexplained cases of decompression sickness. I think it's genius.
" I reckon that bends are like a curse that swims around dive sites. One is formed when someone does something stupid, rapid ascents, missed deco etc. Sometimes they dont actually get any symptoms so their bend is still in the water, swimming around waiting for a victim. An innocent diver just happens to go through a patch of murky water and blam, you are bent"