From: AlecTrevelyan006 | #182
Yet even if Tywin hadn't taken the seat (let's say he went right off to fight Robb), Cersei would have been in full control. So it's irrelevant that Tywin showed up and took control. Cersei would have taken control from Tyrion on her own.
And he could have just as easily gotten it back again. If AFfC taught us anything, it's that Cersei sucks at wielding power.
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"One toot on this whistle will take you to a far away land."
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