Hi,
I am sorry, I just upload another project. Please try look at it again. I just want to bake animation on constrained null (chest_ik_retarget),
which will be correct and not random flips values on Rotation.X curve. I also uploaded the picture comparing bad and correct curve.
This phenomenon has accompanied me for several years, that the rotation of constrained objects in hierarchy to object in hierarchy with other rotated axes, flipping their values 180 and 360 up and down. On the first look everithing looks good, but in numbers it is not good, and I can't save and transfer correct animation. It also happens on native character rigs of Cinema.
constraint_rotation.c4d