You will need to formulize the control points to adjust the curve based on the bezier factor of .55. I prefer to just use the Curve - Interactive tool, as you’re not stuck with any middle points at 180 degs apart as you are with the Spline - Interactive… Generally you’re going to need to consrtuct a lattice on which you can base the width & height of the curve to set the length of the control points.
If you don’t formulize the control points, curves will not adjust to a change in measurement file.