I was JUST thinking about this the other day... we were considering a trip to Jamaica on AA and at the time (2002-3 I think?) AA was about to procure US! If you had miles on US and you wanted to book such a trip as mine on AA, you could use them toward a ticket--like, if it were 35k to get there and you had 17,500 on both AA and US, they'd let you set up the ticket!

We could not go and when we said forget it, they asked which airline we would like all the miles put back into so I said AA.

I do not remember all the particulars on this but that's how I remember it. Would love to meet someone else who had a similar experience and remembers those times.

MM