AA has tried for years to bring AS in, but AS likes the feed it gets from DL and claims to be getting all the advantages of an alliance from its bilaterals. Given that AA gives EQM for AS flights (not just AA codeshare on AS), about the only impact of AS joining OW is the ability to use it for OWE routing. And how much revenue will AS get each your from all those SEA-ANC and ORD-ANC segments? Probably wind up losing money from joining. EI quit Oneworld because of the several million euro cost to update its IT systems to handle JL joining OW (and they expected to interline about 1000 JL pax per year, or about 3 per day). And that was for an existing OW member! AS faces huge costs for integration into OW if it decides to join.