For a marathon, if you're just trying to get your best personal time and don't care about where you finish gun time wise, and the race is chip timed, is it better to start at the back of the pack so you don't have to go slow while you wait for the crowd to disperse?
Also, is there a point where the starting mat gets turned off, such that if you waited too long your start would never be registered anyway? This could/would obviously be problematic.