Boats are fine for very range jobs but the reason why helicopters are used is because of the range. 135nm south Timor for the Bayu-Undan, 210 nm north of the Kimberly's for the Northern Endeavour, 130nm for the Montara field and 254 nm north of Broome for Prelude and Ithycus field and anything from 80 to 160 nm to lay barges. Short range, Pax don't mind the odd boat transfer but long range they hate it.