Flipped keyframes - weird result (walk cycle) I'm working on walk cycle animation for a rigged character and I have a problem.

If I copy keyframes of the pose I made, and duplicate flipped keyframes via Ctrl+C -> Ctrl+Shift+V - I get a weird result, the legs are pointed to wrong directions and so on. 

Why could it happen and how can I fix it?
Thank you in advance!
I believe that is the feature that allows you to copy keyframes and reverse the transformations of bones. Not sure exactly how it works but I use it for walk cycle. It reverses the initial pose of the character to form the middle pose of a walk cycle