I probably miss one flight a year, and it sgenerally due to a traffic accident - either the car I am in or more often some accident which slows down or shuts down a road) and I NEVER EVER shoot to arrive at the airport more than 1:15 before any flight (I actually shoot for an hour). I average 120 flights a year, every year for going on two decades now, this is all about percentages........... If I showed up an hour earlier to each flight I would LOSE 120 hours a year. That is five days out of my life. Similarly I rarely check baggage, and I figure that this saves me at least a half hour on arrival, another TWO DAYS of my life. So between the two that is ONE WHOLE WEEK of my life saved. Therefore if by cutting it close I miss a plane less than 1% of the time, even if I am rebooked the next day (and more likely only a few hours later) I am way ahead of the game!