That's a nice analysis. I don't know HALO definitions, but if I understand you, it is just programmed to recognize whoever entered the master entry code as "Doctor Shin". So when the Ghost breaks the system encryption and opens the door, the code is accepted as an event happening: 'Dr. Shin enters the archive.' Then, when the Fallen follow you in, it reports the security breach to Dr. Shin, as the senior staff present. I'm starting to like this concept; it's a dumb but polite AI which greets the seniormost person who enters their passcode at a given time. If Bob, the night janitor, were the only person entering, it would politely greet him. If Dr. Kozinski were already at work, hearing Dr. Shin being welcomed would let him know the boss had come in (making it a much nicer place to work- no surprise inspections!). But if the project head is already at work, it wouldn't bother to greet the kid who makes copies and gets cappucino for the archive members, because it would be annoying to hear every single person greeted every single time they walk in. Does this sound possible or probable? (The thing that always got ME about that mission- the Ghost actually sounds [i]surprised[/i] that the Fallen followed us in! I realized as soon as I walked in the first time that the door was left open behind me, and was just waiting for the ambush!)