Thank you for reply guys and for the links, I shall check em out.
I was thinking about weights, but honestly it should not break mesh like that.
Also I did edit mesh, weight bones, on a strait mesh before attaching to path. I even adjusted the mesh After it was attached to path and fixed the distortions and still it is janky.
Here is a vid I did of a test.
Please tell me what am I doing wrong. (Chain Scale does not do anything to fix this)