Random query from an amateur observer: What about psychosocial issues in terms of span of control?

From my life experience, limited as that is, I've found that once you get much beyond 10 people (self included), you begin to need to split things up in order to be able to know the people involved (and coordinate their actions) to any substantive level. I can only imagine that gets worse in the environment faced by combat forces.

Is my perspective horribly broken? Is there something I'm onto here?