That's a surprisingly good idea for UAC too. People would hate that it's non-deterministic (from "how will my program run on a user's system" perspective), but

That's a surprisingly good idea for UAC too. People would hate that it's non-deterministic (from "how will my program run on a user's system" perspective), but makes more sense than other approaches. If I'm tapping a file that's been sitting there since the OS was installed and hasn't been touched since... Probably fair to ask me to confirm!