I made a quick trip to Philadelphia over the weekend and realized that Southwest apparently intends to have the highest percentage of on-time flights in the industry. It's pretty simple to do that if you always estimate arrival times that are much longer than you'd need to reach the destination.
On the way out, we were half an hour early getting into Philadelphia. On the way back to Oakland, we were an hour early. In both cases the pilot announced we'd be that early just after takeoff. I certainly don't mind arriving early, but it sure would've been nice for the people picking me up at each end if the original estimates had been close.
On a semi-related note, Southwest seems to be very happy with the state of their business in Philadelphia, but I wonder how well the Oakland to Philadelphia route is doing. There were only about 30 people on each flight. I loved having a row of my own each way, but I'll be less happy about it if it means that the direct route won't last much longer.