2012 Plat
2013 Plat
2014 Silver
2015 Dirt

Couldn't take it any more.

Edited to expand on original post at mkr's request:

Three factors drive my disengagement from United Airlines.

1. Shattered faith in the airline to fly its timetable, keep its promises, or compensate for its mistakes. I and my family had a parade of cancellations, screwups, and other meltdowns in 2012-13 during which UA's apparent reflexive instinct was to deny responsibility, defend its own interests against mine, and fight me (at least until, on one occasion, I got the DOT involved). My service recovery experiences on AA, US, DL, and AS have been far better -- responsive and empathetic. Now I find the mere prospect of a UA flight stressful. I was forced to fly UA SFO-YVR this month because there was no post-dinnertime AC service and worried the whole week in advance, because I absolutely had to be in Vancouver by noon the next day. I looked up all the alternates and next-morning flights and SFO layover hotels in case UA cancelled. I don't have that level of tension flying Alaska or American and I do not need it, or United, in my travel life.

2. Quantitative inputs show United focuses on VFF HVFs, price-driven bargain hunters with no loyalty, but no customers in between -- where I fall. The MP modifications, TODs, all-but-extinct CPUs, unredeemable GPUs, and dilution of sub-GS elite tiers add up to what I call a "doughnut hole" problem for UA. A small free-spending top tier seems happy despite the operational / reliability mess; a large bottom cohort is happy because they got a cheap ticket and possibly a cheap upgrade offer; I am nowhere in this picture. For a flyer with my profile (75-100k BIS miles per annum, 70% business trips, mixed fare classes) the value proposition at AS and AA is flatly, inarguably superior. UA has become like a car dealership that sells Mercedes-Benzes and Kias, but sort of mocks the broad middle of moderately upscale buyers looking for Buicks, Acuras, Volvos, etc. I do not think this is sustainable in the long run but United will do what it will do.

3. A demonstrably dishonest, weasel-minded, adversarial corporate culture that I want nothing to do with. It goes all the way back to "changes I think you'll like" and continues to "flyer-friendly" and blaming weather for mechanicals and crew scheduling snafus so they don't have to kick out a food voucher. I believe the company at its core regards its customers as nuisances who need subjugating, and to be taught a thing or two. When Smisek said the new sheriff in town was going to run UAL "like a business," that was code for saying he owes customers nothing for their money -- not even basic honesty. (How should you regard a company that confirms F award seats, but downgrades you to Y at the gate because, apparently, there was a chance to sell your seat at the eleventh hour to a walk-up offering real money? Such stories, told repeatedly on FT, tell me this airline warrants no trust. None.) This is the only quantitative / subjective factor of my three, but it's how United has made me feel since 2012: angry, exhausted, repelled. So sue me.