Thomas Allen's research at MIT in the 1970s produced a finding that still unsettles open-plan advocates: the probability that two engineers would communicate regularly dropped off sharply once their desks were more than about eight metres apart, regardless of how important their work made collaboration. Proximity beat org charts. The building was the real communication network; the reporting structure was a diagram someone had drawn on top of it.
Desk placement as routing table
Seating charts function as a physical routing table for information — who overhears what, who's asked the quick question instead of the person who's technically responsible, who gets looped in simply because they're near the conversation. Office designers who move a team's desks are, whether they realise it or not, editing that team's information architecture as surely as a database administrator changing permissions.
The doorway as a status field
An open office door has historically signalled availability the way an "active" status dot does today; a closed door signals focus or a private conversation, the physical equivalent of a "do not disturb" state. Open-plan offices removed the doors and, with them, the ability to broadcast that status non-verbally — which is part of why so many open-plan employees resort to headphones as a substitute signal. The information the door used to carry didn't disappear. It just had to find a new object to live on.
An office layout is a communication protocol wearing furniture. Change the layout and you've changed the protocol, whether or not that was the intention.
Remote teams rediscovering "who talks to whom" through Slack analytics are, in effect, redrawing Allen's proximity curve for a building with no walls.