Do you like the idea of connecting in IAH ?
On CO, which is an Amex partner, you can do LAX-IAH-LIM.
35K OP miles for coach
70K " " for BC
Another option is using Taca. BTW, with the programs you mentioned having, you will not be able to transfer points to LanChile.
[This message has been edited by eperaltaotero (edited 08-07-2002).]