That's the closest approximation, yeah. More psychological though. When you're sharing a dream, you're sharing headspace with everyone in it. Brains are messy, they don't leave shit at the door.

[ Like Cobb and his fucking freight train. ]

It was an accidental discovery on the military's end. Recruits were coming up out of dreams knowing personal facts about each other, just from running around in a dream. That turned into another exercise, to see if information could be hidden and then revealed. Or ultimately, stolen.