1. Yes, some pose packs sold have the Hip X, Y, and or Z translated, in order to get the body into the desired position.  This is the only way to get V3 (for example) into certain poses. Using IK on her legs, you can rotate and move the Hip independent of her feet, which is very, very useful depending on what you want to do. But a side effect of this Hip tranlation is if you Y rotate the Body, she will make that circle. 

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