Sucks to be an active participant in this thread. I had a type II hit in Coz. It was unprovoked. I had taken a long walk the night before in the August heat, was taking metalozone ( a water pill) and as was found out later and has since been corrected, I had a PFO. Dehydration + PFO + 4 dives = oh crap. Just got back from Palau doing 3-4 dives a day with no problem. Drank like a sailor (water only), no exercise during trip, no metalazone while on dive trip and I had the PFO corrected last year = no problems 
