Having seen the likely events up there in the past, I will take a punt that it is all about half the runway being on a slop and the top half blind from the taxiway. Combine that with many sloppy radio operators and you get folk taxiing into aircraft cresting the hill either taking off or landing.
The airfield is a great little place but it is far more unforgiving of fools than most others. It makes the blind ends like Bathurst and Toowoomba loo like non events.
As for helicopters at night being a pain in the butt, is there anywhere that Beckers have not worn out their welcome?