Excellent summary, and well done. I do disagree with some of your comparisons to AA.

First, you gloss over the labor strife between Crandall and AA workers, particularly the pilots. I remember that AA had many more strikes than UA from deregulation (1979) until Crandall's departure (1998?). It would be good to get this full list. Crandall ruled over AA with an iron fist.

The labor unrest eventually led to Crandall's departure, along with his perseverance over the proposed AA-BA alliance.

Another difference has been AA's route competitiveness. In the 80s, AA built hubs in SJC, BNA, and RDU. AA pulled out of BNA and ceded SJC to startup Reno Air and RDU to startup Midway (which was Midway 2, but that's off the subject). More recently, AA bought Reno and built up RDU, increasing their presence again in SJC and RDU. But 9/11 has caused AA to retreat once again from these markets.