DLs and the aiming circle
IMHO - We don't need to be too 'dog-in'the-manger' about this lest we miss the most important aspect of the aiming circle and its correct usage.
It is true that when landing on a deck with the minimum 'D' size, when landing on an unfamiliar deck, when landing at night or when uncertain of the obstacle environment, that the correct technique is to place the pilot's bum over the aiming circle. This should ensure that all of the aircraft structure is inside the 'D'. Changing the aircraft heading will be fine as long as the pilots bum remains over the aiming circle and the aircraft centreline passes through the centre of the circle.
There are plenty of other situations when another technique is perfectly acceptable. For example when landing on a deck bigger than your own 'D' size there may be issues to do with the pathways used by passengers and the situation can often be optimised by landing in another location with exits and pathways then defaulting to the safest direction.
When you are based offshore and routinely visit a collection of decks 15 or 20 times a day it is natural for flight and deck crew to seek the safest and most expeditious methods during deck ops but beware complacency, document your protocols so they have SOP status and if in doubt revert to using the aiming circle as described above.
I have found during countless audits that the problems, when they arise, are because pilots have no idea how to make effective use of the deck markings. Non-ICAO markings are often encountered in some parts of the world in which case your FSO/CP/DO must document the correct procedures. Helicopters striking obstacles in the deck vicinity is one of the most common causes of accidents in the offshore world.
G.