Yes it is.
You try fighting at night in a no moon period when its overcast. Even NVGs don't help.
The trick is simply being better by night than the enemy.
Normal NVG are basically photomultipliers, but if its that dark, they don't have anything to multiply as Raven said.
I would imagine there is gear that could do it, thermal vision or active NVG, both of which may are may not be appropriate or available. Walking around with active NVG would be fantastic against poorly resourced rebels, but a giant beacon of a target for anyone else. Thermals are great but AFAIK as a poor layman, suffer from being bulkier, lower resolution, not fast reacting etc. They aren't going to suit every or even many missions.
I suppose you could conduct an operation by beaming in information from airborne/external sensors. Which is what I guess GF was talking about. I would imagine there are very few who train and could do that at this stage (entirely by remote sensors feed).
I would imagine moon timing is also important, with no moon up on a cloudy night blocking star light, it would be very dark, but in a few minutes a full moon can be up and there would be enough light to read a newspaper to.
Any good mission planning should take advantage or work with the natural environment, that includes weather and lighting. The best time really does depend on what your trying to do. An assassin might have the advantage of a total dark night. But when moving a platoon of sof through unfamiliar or complex terrain, more light might be useful.
