Spline Cache Retime Shake

[tomoya kimpara]

Question. 

When I cache a Spline and retime it, I get a trembling line. 
Even if I set TimeStep to 1/2 frame and RetimeSpeed to 50%, the line shakes. 
It also trembles when RetimeSpeed is 150%, but not when RetimeSpeed is 200%. 
Is the only solution to this problem to increase the step?

[tyFlow]

Can you post the file as well?

[tomoya kimpara]

Can you post the file as well?

I am sorry. 
It is a project file and cannot be uploaded. 

Let me simplify and reproduce the same problem.

Please wait a little longer.