They need both carrots and sticks to affect the employee base. No amount of "training" IMO will change the roughly 25% (my estimate) that are apathetic, saboteurs, or freely admit to "hating" their customers.

Unless United gets itself off those most-hated-company-in-America lists and stops leading DOT complaint volume, which it can only do by renovating employee attitude, "Fly the Friendly Skies" is a pretty hollow line.