It is my understanding that C-NLOPB Helicopter Operations Safety Committee have recently completed a risk assessment on the wearing of helmets in offshore operations.
It might be worth reading this report because it takes into account the probability of a pilot being involved in an accident (in this type of operations), the likely benefits, the physiological effect of the wearing of the helmet on long sectors, and the likely long term effect on health.
Whilst a good case can be made for the high-risk short-sector type of operations, it is not clear that the same benefits obtain for the low risk, long sector, operations that apply offshore.
Perhaps the discussion should be driven by the data - not emotion.
Jim