Great post, OP, because I have suffered this problem too (AA, it isn't a Delta unique problem). It's a great example of how a law like EU261 would really help premium passengers in the USA, since on EU carriers (and ex-EU flights) a downgrade in class of service is worth 75% the price paid as cash (not a price difference/refund or comp certificate). And keep in mind, inside the EU "business class" is just an economy seat with a blocked middle, so it isn't even as big a downgrade as it is to F passengers here in the States.