I just have to say that IAD ground crews are the "joke" here, not the Mesa crew. It is very rare for ground crews at IAD to get you pushed back for an On Time departure. Just because someone is "new" or on IOE doesn't make them "unprofessional". I don't work for Mesa and I haven't really ever had a bad Mesa crew (deadheaded on them more than once), in fact, I've had much worse service from mainline United FA's (one FA even went so far as to accuse me of smoking in a bathroom, when I had actually had a smoke in the reserved smoking row before using the bathroom (it was a flight from Tokyo to Hong Kong and they reserved the last row of seats for people to smoke, at least they used to back in 1994) Obviously the majority of FA's I have experience on mainline United are very professional and courteous, however, it does show that it isn't just Regionals that may have an "unprofessional" crew.