When things go badly wrong, why does it always have to be someone else's fault? Why can't people take responsibility for themselves?
     Blackford and I still vividly recall the day when we watched other passengers on a boat get ready to dive in conditions that were obviously dangerous.
     The boat was moored in a big swell. We could see the seabed alternately coming up to within a metre of the stern of the boat and then dropping away beyond the range of vision.
     Getting in the water might have been easy but getting out later would risk having the whole boat descend on our heads as we went for the stern platform.
     Still, everyone got ready without hesitation, despite our observations, and all went diving. Thankfully, no-one was hurt.
     Had there been injuries, would it have been the fault of the skipper for putting them in there? Of course it would, but then again, no-one forced them to go in and some of us tried to deter them.
     These divers were ready to abdicate responsibility for their own safety.
     How can a fit, healthy man drown during an ordinary leisure dive? I will shortly be called upon as one of a number of witnesses to answer that question at an inquest. I have my opinion, and will explain the situation as I see it, based on the facts I had to hand.
     But I will do so in the knowledge that the dependents of the dead diver are, understandably, likely to be assuaging their grief with the idea that someone else must be to blame.
     It isn't always so. We live in a new age of legal liability. "No win, no fee" lawyers stoke the fires of legal action. Insurance companies may find it cheaper to settle out of court than pay their lawyers to put up a fight, even if they know they will win.
     Death is not an optional extra to life. We sign up for it the day we are conceived. Death and injury are part of normality. All we can do is delay the inevitable by making risk assessments.
     Deciding whether to take a risk is an everyday occurrence - you do it every time you get out of bed. In fact most accidents happen in the home, but who are you going to sue?
     My first dive in UK waters, around 20 years ago, was on the wreck of the Kyarra, near Swanage. I had done some 500 dives in warmer, clearer waters so my technique was OK. I just needed to get used to the poor visibility.
     However, I reflected at the time that if I were my buddy, the girl with whom I had been paired to satisfy some notion that every diver needs a buddy, and who was doing her first sea dive, I'd have turned back and decided to do something easier.
     I hoped that she was not down there with me simply because of peer pressure. Later she said she had enjoyed it, but I'm glad it wasn't my first sea dive! I might have been writing for a gardening magazine now.
     My friend Rob Palmer went missing after last being seen at around 120m, waving to his companions to come down to join him. Mercifully they had second thoughts, two of them belatedly turning back at 108m.
     Later, as a result of that tragedy, my non-diving mother-in-law decided that her grand-daughter should not be allowed to put her head under water. After all, you can drown in the bath, and she saw no significance in the actual depth.
     Water is water and, yes, more people probably drown in the bath than during dives in excess of 100m while breathing ordinary air. Perhaps she had a point.
     When you learn to dive, you put your life into the hands of strangers. Your instructor has a duty of care because you know nothing about the insidious dangers to which an untrained scuba-diver might be subjected. But later, accepting certification means accepting that you know something. Certified divers are meant to have diving knowledge appropriate to their certification.
     I'm not saying that it's your fault if a skipper reverses over you during a normal pick-up. Everyone has a duty of care and people can be negligent.
     And if someone is incapacitated and unable to make decisions for themselves, woe betide another person who might make a wrong decision for them.
     However, when a life is lost, it seems natural to look for an outside force that might have influenced the tragic outcome. Faulty equipment, inattentive buddy, incorrect dive briefing, poor dive marshalling - they can all be questioned.
     What rarely seems to be questioned is the good sense, competence, preparation or performance of the lost diver. Sadly, a common cause of death is misadventure.
     No one makes you dive, so you owe it to yourself to take care. Be aware of the hazards. Take precautions. Get the right training. Make personal risk assessments. Take responsibility for yourself.
     As Rob Palmer used to say: "Anyone can call the dive at any time."
     It was also Rob who said: "Get it wrong and you're dead!"