> But how do you know which interactions are useful to your business and which are not? How do you the right amount of flow through an area? What about the things you can't measure, but may matter to the health of your workers?
For most people, using their experiences throughout their life as a perspective. Once you get into a new workplace, you can use those years of experience as a basis for perspective relative to the observations of the new workplace. For a lot of people, their intuition makes this kind of thing obvious once they start looking at the data and look around casually in the workspace with note of looking at the people, their movements, and what they're doing. It's the kind of thing that after working at a new place for a week, I already would have a solid feeling and a useful perspective — not just from the new workplace, but comparing that new workplace based on my experience of other workplaces that I've worked in, consulted for, and otherwise visited.
But, there are formal studies on human interactions in the business workplace addressing all three of these questions. I don't have particular citations of interest off-hand.
> I still don't see how knowing stair steps in isolation will generate any valuable insight.
Strictly empirically speaking, it doesn't really. However, this set data from one location combined with observational perspective of the people within the space, could easily lead to more informed conjecture and related hypotheses.
However, the novelty of the single location data set may be as useful distraction; to serve as an element introducing "fun" and "amusement" into the workplace at acceptable levels of "fun" and "amusement". (There are studies on this, as well. This information can serve as a device to break monotony and a "humdrum" atmosphere. You can employ other devices as well. For example, free soda can be used as a device. Whether or not that device works effective and the full consequences (positive & negative) is beyond the scope of this simple comment.)
If you want to pursue this beyond typical intuition, I recommend taking human behavior studies in psychology with respect to interior design and architecture.
This goes beyond just traffic flow, but incorporates other aspects of the environment and its influence on humans.
However, you don't need to have academic training to be useful. Many people have the intuition to reasonably and appropriately make observations, analyze, and comment on their surroundings.
But, on the more academic side of things, here are some quick and dirty Google search results. Random examples of literature in ballpark of this field in an assortment of contexts:
A Homely Approach is Paying Dividends for Patients and Staff. (2012). Nursing Standard, 27(2), 20-21.
Rydeen, J., Erickson, P., & Lange, J (2008). Built for Brains. Industrial Engineer: IE, 40(3), 32.
Joye, Y. (2007). Architectural Lessons from Environmental Psychology: The Case of Biophilic Architecture. Review of General Psychology, 11(4), 305-328. doi:10.1037/1089-2680.11.4.305
Read, M., & Upington, D. (2009). Young Children’s Color Preferences in the Interior Environment. Early Childhood Education Journal, 36(6), 491-496. doi:10.1007/s10643-009-0311-6
Moore, G. Architecture and Human Behavior: The Place of Environment-Behavior Studies in Architecture. http://sydney.edu.au/architecture/documents/staff/garymoore/...
Cummings, N. Fostering Sustainable Behavior Through Design: A Study Of The Social, Psychological, And Physical Influences Of The Built Environment. http://scholarworks.umass.edu/cgi/viewcontent.cgi?article=20...
Esmaili, Y. Consideration Of Human Behavior In Designing A Green Office Space For Environmentalists A Simulation Study. http://architecture.arizona.edu/sites/default/files/faculty_...