Well, I missed the class in which we "creeped" the halls for poor unsuspecting souls to whom we were to ,listen to. However, I did happen to have a friend explain what was done and did something similar elsewhere and at another time.
Over the weekend I finally got a chance to do this "Experiment" and Followed a couple in the Portage place mall, I eavesdropped on their conversation but lost track of time. The Man And his Interlocutor were both conversing on their work days... or nights, since they sounded like they work at night, conversing about their bosses and their co-workers laughing and giggling.
During the "investigation" I was having so much fun, as if I was detective Cole Phelps from the game L.A. Noire. During this ultra intrusive session of awesomness I did things that normally I would never think of doing.
A few times on their exploration they turned around to head a different direction and check a new store. When this happened I would dodge and head into the nearest corner to escape their gaze, once I said hello to a random group of people standing off to the side as if they were close relatives to ease the couple's suspicion (the group I greeted was confused but understanding when I explained). The couples conversations were all over the place, quickly switching between their kids, plans for later, work, and "squishy" talk normally said between young married couples.
If I was to apply only what I have learned from the conversation into my writing I would have a hard time keeping the reader interested or focused on the story due to its seeming randomness however I could use similar emotion, and personality in writing to describe a scene or a multiple character conversation.
From what I saw and personal experience in conversing, regardless of the personality there is "Switch-back" between the interlocutors, quickly "switching back" and forth from topic to topic.
I would have to say this "mission" was a success!