Why would they do that

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Because if they vote 2 for Genevieve, 1 for Joe then if Aubry plays her idol and Genevieve doesn’t, Genevieve goes home. If Genevieve plays an idol too then the stray vote would send Joe home. Alternative versions include putting 2 on Joe, 1 on Genevieve for a safer play. It’s not 100% guaranteed but there’s no upside to putting all 3 votes on 1 person

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