Extended Perception Check, How long does it take to notice something? Options

[Thorguild]

Apropos of nothing: How long before a mage who occasionally astrally perceives notices strange things around him?

Scenario 1: A university mage has a secretary named Sue who is a secret Technomancer. The mage has a total of 8 dice in Assensing, and has no idea there's anything weird about his secretary. It takes 5 successes to find a TM.

He goes about his daily work, which includes spell research, publishing, fundraising, grading papers, teaching, and office hours. He uses assensing in short bursts on a regular basis, and has no reason to assense Sue. Sue works in the same small office and is up and around while he works. He chances to glance at her occasionally while assesning other things.

So the rules would say that he never notices that there's something strange about her, as he never Observes in Detail. A Hand Wave says that he gets it when the plot calls for it.

Does anyone have another take on it?

Scenario 2: A security mage does irregular sweeps for invisible intruders. He walks through the cafeteria while 50 workers are eating. He's not looking at them specifically, but sweeping over EVERYTHING in an alert but perfunctory manner. What's his chance of catching Sue?

Scenario 3: A student mage has a crush on Sue and takes every opportunity to watch her. Sometimes he assenses her in detail for a long time. He has 5 dice. His chance to get 5 successes are about .004. His Glitch chance is at least 4x that. Does he get any bonus because he's staring at her doe-eyed for a long time? Like an extended test?

What do you think?

Thorguild