Hi all,
keep in mind that I am still learning Blender...

I have an armature (rig of a belt). All bones are keyframed in Quaternion mode (and not any other mode). The exception is the Base bone which has also keyframes in other rotation modes (XYZ etc...).
I don't know how this happened, I probably made a mistake at some point.
Two questions :
1)Does it hurt to have keyframes for the different rotation modes on the same bone ? Should I clear the keyframes in all modes except quaternions for the Base Bone?
2) For that Base Bone, when I go from Quaternions to say XZY, the belt is rotating and when I go back to Quaternions it doesn"t go back to its original location ? Only crt-Z will bring it back. Do I miss something here ?

Some pictures (Base bone selected in all):
Quaternions are keyframed
Click image for larger version. 

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XYZ and other modes are also keyframed
Click image for larger version. 

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Going to XZY mode rotates the rig (and doesn't come back to its original location when going back to quaternions mode)
Click image for larger version. 

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