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I tried to reproduce the pose you showed.  I have similar result but the problem can be reduced by adjusting the combination of lCollar and lShldr bones.

That is usually my suggestion. The JCMs are not perfect, but it often helps to consider how much a real limb could bend in such a pose and avoid going past its natural limits. That is true for any figure.

That said, with the arms one really has to fiddle a bit to find settings that work well.

-- I'm not mad at you, just Westphalian.