Split existing segment(s) with additional control points

[KStress71]

Is there a way to insert new control points into the middle of a spline?  Or possibly auto-split an existing spline or segment into a configurable number of segments?  I have a spline that I've created to represent a train track across a terrain, but I need more control points and would prefer not to add on the end and reposition all of the existing control points.

Thanks in advance!