Sorry, Flying Bull, my reference to NVG flying was historical. I started flying on goggles way back in 88, in Germany, when we'd do 3-4 hours continuous, both in the simulater and actual, to build up experience. I can't reach my logbooks at the mo, but I'm sure I've logged 6, 7 and possibly 8 hour night duties, all actual, in other places.
The crews are quite possibly restricted on how many hours they can fly at night - I know that in my time, the night route system was becoming restricted out of consideration for our host nation's citizens.
As for the point about neck injury and the strain imposed by the goggles, it wasn't something I came across during my time in, but as has already been alluded to, us Lynx drivers are generally built like props, as distinct from the 'winger-like' svelte floppy pilots.