I'll just add that with EU passport, if you can, you want the first door of the second car or the train to T4S. The door will open to offload on the opposite side. Just that alone can save you a few minutes at passport control to be first in line. Also, if you see open lanes and people in front of you aren't moving and you're in a hurry. Just go. For some reason people are completely incapable of going to clearly open automatic passport control gates unless some security guard points.