When I had that experience it was because the (Continental) plane had never left Houston for its round trip to Cozumel. We got our checked bags back for the night, and the next day when the plane was finally coming we had to check in all over again just as if the day before had never happened. And yes, it was a separate flight; if it was a daily run there were two that day.Was it? Did the passenger have to go through check in again? Did they have their checked bags or just the carry-on? It had to be a separate flight. I've never been on a flight so empty - even last summer - that could absorb all the passengers from another flight.You might have noticed the flights are running pretty full.