Only just saw HeliComparator's reply.
The IFR fuel requirements are the reason we don't file IFR on our off-shore flights (you are correct, not in Europe). Since none of our off-shore platforms have fuel we have to file to return to base (which would be our on-shore alternate for any of the off-shore sectors)
plus for an on-shore alternate to our base. Plus of course holding etc. Our usual loads have us going out at close to max weight on VFR flight plans so carrying IFR fuel would make a serious dent in our ability to carry payload and/or make long (multi-sector) flights. The weather tends to be good, allowing us to fly VFR so much of the time that delaying/cancelling the flight program due to IFR conditions is not a problem.
Also, if every approach had been flown as an IAP rather than visual on the mishap flight, that would have added substantially to the flight time, probably 4 mins. per sector on average (if the IAP were to have been flown into the prevailing wind, our company SOP for ARAs). On an 8-sector flight with 7 off-shore approaches that's about 30 mins extra. Extra fuel, less payload. Same fuel, fewer sectors.
With my limited night off-shore experience I have concluded that never was a truer word written than
Only pilots disciplined in instrument flight will survive
and indeed that's how we do our night flights, with the PNF remaining on instruments, constantly monitoring and giving verbal cues to the PF, and ready to take the controls for a go-around on instruments. I also agree that
a great training aid in this area is the simulator, despite any limitations it might have for night visual approaches to a rig
I maintain however, that the aim of this training and discipline should be to position the aircraft at a point, height and airspeed, that will allow a controlled visual descent to the deck (or go-around) and that this point, height and airspeed should be the same every time.