MileCrazy: Thanks for the refresher. I am just about to book a flight STL - MEX and I did not remember the double miles. You just saved me about 3,500 miles. Thanks.

Regarding the MSY - MEX flight, I understand from a TWA press release that the flight originates in NY at JFK. Thus it is kind of a continuing flight that has MSY conveniently right in the middle of the route.

If you're interested, see:
http://www.twa.com/pressrelease/docu...iReleaseID=439