I think the Citadel works best after the credits roll. Not only is it completely separate from the ME3 main plot, the tone doesn't fit in this third act at all. It's basically a love letter to the fans, a farewell to the Mass Effect trilogy. I'd much rather say goodbye to the series with a fantastic piece of DLC than with the actual ME3 ending.
@matoyak: You're right, they're not identical. English is only a second language to me and those sound really similar to my ears, maybe dual is a bit longer. But anyway, in the hungarian pronunciation Hungaroring is supposed to sound like "bush" or "full" or "put", these may be better examples.
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