I think the key is anticipation of potential problems. Frex, I've noted that many folks who wish to change lanes drift toward the lane they're headed for when they check the mirrors or turn their heads. This is a variant on target fixation - they are moving the way their head moves like a horse.
Anyway, this tips me that the cage will probably soon change lanes (signaling or not) and that I need to make sure not to get in its way. Another danger signal I've seen is when a cage is entering your roadway either from the right (or the left to turn in front of you) and you note that they are NOT looking at you. To me, this is a huge red flag.
Why be born again when you can just grow up?