Two things to add from my experience: one, you can often look ahead to see if fast-track security is actually faster than regular--sometimes it is, sometimes it's not. This can involve making an informed decision with respect to the sorts of people in line too--how long you think they'll take; that is, how experienced they look.

Secondly, most Flyer drivers (and I myself) know where the common radar traps are. That said, they can (and will) get you anywhere. Cash cow I guess.