I do feel a drill to remove the target from the threat is primary. With a large group this is difficult, but can be done if one has control of the building and all are familiar with it. Heavy, lockable doors to classrooms(we had these when I was a kid nearly sixty years ago in hurricane country) and retreat rooms. But PREVENTION is key.
The primary fault with the concept is assuming "HOSTAGE SITUATION".
Assuming "the bad man will be nice if I do as he says" will probably turn out badly. What tactics are going to work that are worth risking the lives of the hostages? It's a huge disadvantage.
Avoiding a hostage situation is primarily accomplished by hardening a target. Providing an armed guard, and locked doors, rather than accepting the scenario of being taken hostage is what works.
Introducing a hole card, an armed guard, short circuits the threat in most scenarios.
Thanks, God Bless

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