I was looking for a similar script but had no luck.
I have a lot of closed Subsplines for Windows/Doors and I want to select/detach some of those within the specific range looking as RC X-->XY workflow.
I know it is an easy task just to set some Conditionals and filter them within Style Editor but usually, I`m preparing RC Presets for end-users so often time I`m requested to create a "Single-Spline Type" preset.
Hope that makes sense.
I think the script could look like img attached. Inputs for the range and small +/- Threshold to make sure to catch small deviations in size.