My comment with regards to cancer was slightly tongue in cheek as you gathered but it does raise another useful illustrative point. In fact the current risk of dieing from cancer during your life time if you are a male is 1:4 - slightly better odds for a female. The life time risk is therefore high. We spend very little of our lifetime flying a single over the water and certainly not a life time. So is the average GA pilot more likely to die of cancer or from ditching - without doubt far more likely to die of cancer. If he spent his lifetime flying over water, you would arrive at a different conclusion.
With regards to most accidents being caused by the pilot or avoidably poor maintenance I dont think we need the stats to support the premise. If you read the reports it is apparent just how many pilots are candid enough to admit the accident was their fault - by extrapolation one suspects that this would be equally true of those that sadly kill themselves.
However I do agree that there are many myths that should be challenged.
There is much written that cannot be supported in just about every walk of life. I certainly dont have all the answers but have taken a little interest over the years in the stats that are published and are relevant to the things that interest me as a useful basis for hopefully adding some susbstance to a debate.