Curve tools: is there an add-on to join overlapping curves? In a "Curve" object that contains several non-continuous curves, is there an add-on to join overlapping segments together, like remove doubles does in mesh editing?
Explanation: merge two non-continuous segments with two control points in the same place so they become one unique segment!

I have this solution: I move one control point, then select the second contol point and press F to create a new segment that connects the two together. Then I remove the previously moved control point with X and both segments become one unique segment!

I can add a new add-on with this process, but I want to know if this command already exists.
There is no function that does this. If there were it would be Merge (AltM) as can be done with vertices in a mesh object. Ideally this command should be coded into Blender natively without needing an add-on as it's such a minor operation. It would only be possible with two open-ended points though, and maybe that's the reason it hasn't been included thus far. 

I suppose having an error message appear at the top of the screen when the points are not open-ended is one approach; another is breaking an existing segment in favor of forming the new one.