I've watched a presentation on this problem that showed surveillance footage of this exact kind of situation happening and costing the lives of at least two peo

I've watched a presentation on this problem that showed surveillance footage of this exact kind of situation happening and costing the lives of at least two people (I think the fourth one realized what was going on and got geared up before saving the last one to go in before him). You could watch them simply drop like flies, it was obvious they didn't realize what was happening to them before they fainted.