Twice I have been late for flights at SEA, with the aircraft leaving in under 30 minutes, by the time I arrived at security. I was on domestic flights in economy, and had no status that would get me through fast.

I went to the elite line and politely explained my predicament. Both times, without even a word, the nice people let me through. First time I made my flight with time to spare. Second time, TSA picked me out for secondary screening.

In short... the elite line should stay that way. It is after all for the frequent fliers, the high revenue pax, and those who practically live in the air. But I see no harm in allowing people to use it if they are running late. Fair use of course.

A really great system here in Amsterdam Schiphol is Privium. It uses iris-scanning technology to allow one to bypass immigration, but there are also dedicated security lines as well (or the pax are whisked to the front of the normal for the unwashed masses). I've seen people get through in less than 2 minutes. I imagine if one does it right and prints a boarding pass at home and has no check-in luggage, one could get from train platform/curb to gate in five minutes. There's no way to beat the system either (unless you steal someone's eyes)... plus you get business class check-in privileges at many airlines and priority parking. Truly fantastic system...