Just an aside,
In the RN we were only allowed to transfer passengers at night, over water if they had completed dunker training for underwater escape. Fairly sensible approach considering the only people to get out of the Scilliy Islands S61 were dunker trained.
As to rig approaches at night then I, personally, don't see the problem. As long as the flight is well briefed and one of the pilots is experienced there is no difference in a rig approach than to, say, a tricky confined area landing or a night deck landing.
Experience is the key here, as the airlines soak up the experienced pilots due to better T&C's (hard to imagine but alas true, me included), better working hours and a more stable roster then the guys/gals left flying the line will suffer from the loss of experienced pilots. With the current down turn in the aviation industry it will be interesting to see if people will move or 'ride it out' with their current employer.
W2P
(2000+ deck and rig landings
)