Neither a seniority or a merit based system would or is totally fair. I have worked in both and see the advantages of both. I will say that it took awhile when I first went to a seniority based system to get use to the idea that how well i did my job had virtually NO impact on where I could be based or what aircraft I could fly. I understand it, and you have to work that situation, but at the end of the day, it is what you make of it. I could envision much worse systems than seniority based.