I don't know how many here have done many photographs of groups. Not just "candid" shots but set up shots, as this one is.
He obviously didn't just happen upon this scene, and it almost sounds as if some people here are "disappointed" that he controlled the elements here.
When I look at commercials and movies I always like to disregard the main subject and look at the "atmosphere". The people that wander through the scene, or are in the background, and observe what they do. As someone who worked in the movie/commercials biz to a very minor degree, I learned to appreciate the quality of a director by how well he choreographed the "atmosphere" people. A TV show like the West Wing that has dozens of shots of people wandering around in the background in every episode, is an amazing accomplishment.
When I look at a picture like this Strand picture, I always imagine the blank slate he started with. How he arranged the elements, where he put people and why, how he used the pecking order, and finally what he was trying to say. As I mentioned I've posed hundreds of groups from familes to wedding parties, to a couple of hundred employees, and to more intimate emotional arrangements where people interacted with each other and not the camera.
The question is who should I put where and why. Once that is done, where should they be looking and why. Every one of these things come into play in a group type shot, whether it's this type or any type. Remember before he started he had 5 people standing around staring at him, and he had to take charge, and put it all together. And at the same time justify his decisions.
I do find it interesting that people don't really like it being over analyzed, when in fact the photographer had to do just that when he took it. And he may well have taken it with them looking in different ways in other shots and like this one better.