Uncle Pug:
1) *The degree of vigilance* is not onerous as you assume. It can actually become an unconscious awareness ~ connecting you to everything else on the dive like a spider's web. You feel the tiniest vibrations in the fabric of the dive. You focus on one thing but still see all.
Limeyx, most often with my regular dive buddies, we all have small cameras. Some are even waterproof.
I believe you are describing the "force", oh master yoda. You need to loose those neat dry-suits first, then you can be one with universe.
I love that photo, by the way, even like the uniforms - reminds me of diving in the military, except your stuff is pretty (blue, you are allowed blue?).
That sure must have been a scary dive, what with the water and waves and rocks, oh my. Sort of tiny waves, though, but the fog was scary. Try jumping out of an airplane at night, in the middle of the ocean, into 30 ft swells.
You, and many others may think you are totally aware of everything around you, but it is really easy to show that is not true. You just think you are.
When one is trying to capture a picture of a moray, with just the right mouth opening, it takes minutes to get the right image. During that time, like it or not, the person is in their own world. At that time, they have no buddy, they have no DM, what they have is their own world and the fun of getting the perfect shot.
Funny thing is, that same situation can happen to people without a camera. Say your suit inflator sticks. At that moment, your buddy's getting attacked by a shark. Neither is being much of a buddy to the other at that moment. Most UW photographers are honest and admit it, other, not so.
One of the really good lessons the military taught me was that there are things you can handle, things you and your buddy can handle and things you really really hope never happen. Planning only goes so far.
UW photographers, good ones that is, usually make rotten buddy's, but they also tend to be great people, with a great love of the world around them. They also tend to be more sensitive and more aware than most "normal" people. True, they are not much into hand holding, but they see and feel better than most.
Because they are, at times, solo divers, they also tend to make much safer dives, and are more careful about condition. Making sure that the conditions and their equiipment are right for the dive is not such a bad thing.