True. As both of these carriers are already aligned with Star(the only 2 US airlines so aligned in fact) and, as you pointed out, there would be a reduction in capacity that would follow, it would result in only one afilliated US airline, however large. They also would maintain (almost) no connecting options for international arrivals in the NY area.

Does anyone else envision a door opening for B6 at the same time the one closed on the other side of the Hudson? Had CO merged with UA they would have most assuredly been enveloped by STAR and would have been strong in NY as well as still maintaining US's network. In this scenario they would still maintain US's network but NY is left in a (still) troubling position.

Regional members have been brought into STAR to serve a purpose in the past. Is NY and a second US airline option(assuming a US/UA hookup) a big enough purpose for LH and STAR?