I take the Delta shuttle between NY and Boston all the time, and I can tell you that the increased traffic on Amtrak is a direct result of the airlines horrible on-time record, especially in the summertime. Just the hint of a thunderstorm means your 6:30 flight will be delayed 2 hours, at least. I know a lot of business travelers who are going for the Acela instead. I would too, if my company let me.
My wife travels a lot on business. Missed connections, delayed or cancelled flights adds up to many hours sitting around in air ports. 22 hours from Burbank to Chicago is one example, when she finaly got to Chicago her flight to our area had been cancelled, it was either get a motel, stay in the air port or rent a car for the extra 200 miles home. She rented the car.
That was not an uncommon occurence either.
She flies either American or United because that's the ones her company has contracts with.
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