Oh, BRS is dreadful too, except if you have clued up people running the gate. Unfortunately there's only a couple of those
I applauded one of them once for announcing, "I've called group A which consists of 30 people; there's at least 70 of you in the queue; when the 40+ people in the queue who aren't in group A leave the queue, we'll continue to board."
Can't do it all the time but it only takes a couple of times to start getting the message across. At the old D gates at AMS they sometimes used to simply impose a rule that if you came up too early you didn't just have to wait until your group was called, you boarded last; hardly added to the overall boarding time, just inconvenienced the selectively deaf.