.
I did notice that from the personal accounts inside the theatre ... many concert-goers were "frozen in shock". it is that weird psychological shock that happens when people see things that are completely outside their experience. The survivors literally had to climb over 'frozen people' to escape the scene. Those that did MOVE had a better chance of survival. But there is no easy answer for this ... that tendency to freeze is deeply ingrained into our subconcscious and it takes a lot of willpower to "un-freeze your body" and get moving.
Pete
It's been discussed in this forum before, but it's worth mentioning again because of it's relevance to the surviver accounts. Amanda Ripley's "Unthinkable", ISBN 978-0-307-35290-3, covers the fight/flight/freeze/flop reaction in depth.