Dune, for people hired in '04 and '05 it worked quite well. They're most probably now captains and "enjoying" being constantly second guessed now.
I most certainly second most of the sentiments aired here (since I have to sit next to people who would not be captains under the new rules but still are; and have to make up for their lack of experience) but do not forget: you are an expat.
I have never for a second bought this B$ about "finishing your career" at EK. You are an expat and you're here for one reason: To be a stop gap. But, and I'm sure EK Management realises this too, this is a two way road. I for sure will leave here as fast as I got here when openings will come up in a year or so. Unless they pay me to stay, that's what expats do. And if they do not, well, a couple thousand hours of WB intl. experience will be worthwile when all those geezers finally retire when they turn 65...
But for now management has decided to go for the short term budget saver than for the long term career builder. They'll reap what they sow eventually.
As far as the reasoning for the FCI, well that's an easy one: Since they do not need that many Captains anymore they might just go for the more experienced F/O's and DEC's.