What reason would Edea have for wanting Adel free? Remember in the game, (SPOILER)she accidently gives Rinoa her powers (in Esthar, visiting Dr. Odine). If anything, she would know that the event happened and possess Rinoa instead of Adel at that time. That doesn't make any sense.

And the Well-Organised-Time-Compression is secret, but it's a key factor? The story seemed clear enough to me, even if it was complicated.