[toss1]

>>every group is different, has different needs, and will respond differently to different styles of communication

YUP!!

Especially when some parts of the group are working with Controlled Unclassified Information (even more so for classified); it's a legal requirement that people access it only on a need-to-know basis. Even without that, companies that rely on trade secret protection (Apple, SpaceX come to mind) must also compartmentalize their information both to prevent leaks and to protect it's legal status as a secret (you must treat a secret as exactly that, or risk it being declared public domain)