There is a massive difference in the rate at which airliners end up in the water compared wih offshore helicopters (over 1000 times..). Hence the concentration on survivability with helicopters.
It would be very good to reduce the frequency of these events occuring to offshore helicopters, unfortunately the introduction of the new types has actually reversed what was an improving accident rate.
Some of that has been down to mechanical issues, the others down to operational ones.
What is inescapable is that accident rates vary across the world. In clement areas a ditching is a real inconvenience and not necessarily even reportable.... In our neck of the woods it is another matter, read the report on the ETAP ditching and note that although recovered in less than 2 hours, many of the passengers were severely hyperthermic.
The thing that really occupies my mind is the apparent difference in rates between Norway and the UK. The somewhat adversorial relationship betwen contractors and clients and what seems to be a lack of real safety leadership - from either side, appear to have created a needlessly dangerous situation in the UK. Reversing out from there will not be easy and at the moment there are no obvious champions.