Flown Cathay RT Hong Kong to ORD many times, connecting to American for a short domestic leg to OMA after 7 day Chicago stopover. All four legs one itinerary booked through Cathay, so Cathay's trans-Pac 2 free checked bags allowance applies throughout. I'm now in Taipei, for the first time flying EVA direct to Chicago 9/11. Despite EVA's Star Alliance partnership with UA, EVA's booking page, set to multi-destination, would not connect to any US flights beyond ORD. Went to EVA's main Taipei office, but they suggested UA was blocking further US connections. I thus had to book EVA and UA legs as separate RT tickets, though in fact all one itinerary with coinciding dates. I promptly emailed UA Cust. Care exec. level (per your good list). Respondent polite and articulate, but first said stopover voided MSC baggage allowance. Plainly incorrect as all my HKG-ORD-OMA flights, including ORD stopover, enjoyed 2 bag allowance, and DOT Most Significant Carrier bag rules are explicitly not voided by stopovers. I wrote her back, very politely saying so, but attaching DOT Section 399.87, with its notice of $10K USD fine per incident for airline failure to honor MSC bag regulations. (This includes foreign airlines operating in US under US tariffs .) I'm aware my upcoming itinerary can be considered two since booked "separately", but this spliting was created by the airlines' own booking issues. The UA CC woman claimed no responsibility for failure to link EVA/UA itinerary, saying I'd need to pay bag fees for both UA legs. Hence each carrier seems to be blaming the other, while I'm stuck with a $140 UA bag fee for two bags round trip ORD-OMA-ORD, despite the entire journey clearly being one itinerary. Not sure who's at fault here--incompetent IT at EVA, or UA stealthily blocking EVA connections in the US in order to assess improper bag fees. Before filing a formal DOT Air Travel Complaint, I beg the opinions of more knowledgeable travelers on this site. If EVA's fault, I may simply have to find another airline that will fly this route as one itinerary.