interesting last night on the LHR to basel. gate B42 (i think, too much CCR chablis) and the gate was quite crowded but worked my way to the front as they were quite strict in letting people thru the barrier. scanned and held in pen with loads of others and they kept calling the groups in order but we were not yet going down so i wondered what the purpose was.

well once we were allowed, the agent turned on the escalator and announced group 0 only, and on we went and then 1 etc. so it was nice and orderly despite my initial wonder it would be a mess.