swordsman - FWIW the easyJet command system is effectively a seniority system too and no 'brown nosing' is required. The reason it is effectively a seniority system is that throughout the 10 years + of its existence there has been a suction process into the left hand seat due to continual expansion. There has been the odd halt in commands at different stages but not for more than a few months. That means that if you had the hours and the grades in the simulator plus you could convince your base captain you were suitable, then you were put on the Command Course. The date of the Base Captain's interview (known as a 'CPI' or Career Progression Interview) is the date you are added to the Command List. That list determines the order you go on the course.
I would accept that we cannot go on expanding for ever and a time will come when 'dead man's shoes' will apply (just like BA). At that moment the current system will look even more like a seniority system except the Command List will take years rather than months to go through. Personally, I fully expect a recognised seniority list to come into play at that point, but that is effectively what happens just now and no one is disadvantaged on grounds of seniority. Like every airline you still have to produce the goods and people do fail for one reason or other. Nonetheless, my observations over the last few years tell me everyone who is up to it gets a crack at the course when their turn comes round.