<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by Snowdevil:
The third piece thing was from WAAAAAAAAY back, when customers were permitted a third piece if it meant they wouldn't have a carry-on bag.
Unless I'm mistaken, that exception is occasionally permitted still, but only on EXTREMELY full flights where overhead space is at a premium. Odds are it doesn't occur that often now that the TSA has regulations permitting only one carry-on.
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Actually it's new with the new weight policy of Oct 1. A new baggage fee screen pops up when excess bags happen. There's an exception there for "gate checked" item. Of course, this doesn't mean you can check 3 and still have a carry-on size bag on the plane.