I don't think that these are seen as tactical devices, but rather as administrative devices. The bulk of an officer's or NCO's job consists of taking care of h

I don't think that these are seen as tactical devices, but rather as administrative devices. The bulk of an officer's or NCO's job consists of taking care of his people: leadership, training, and management. If everyone had one of these, they could potentially be a very valuable tool for maintaining accountability (military-speak for knowing where everybody is), disseminating instructions and notices, and other mundane administrative and management tasks that take time away from more important things like training and maintenance.