Yeah it really depends on what the user wants for output.
And yes Joe. Belt and suspenders.
For the curious here's a couple of ways to make zero length objects.
1. Draw a line 5 units north
2. Draw a line 5 units east from the end of last line
3. Fillet with a radius of 5. The two lines turn into zero length lines at the arc's endpoints. Select them and check thier length. Now try this with plines and you will see they are still created but they are embedded in the pline. Explode the pline to select them.
One of my favorite noob moves. Don't think this still works in 2012 and up but if you have 2011 or earlier,
1. Begin to draw a plane. Start any where and form a triangle. When you get to the last segment, snap to the start point and then hit C to close.
By default C3D 2012 and later will prevent you from snapping to the startpoint but you can trick acad by starting at the endpoint of another object.
John Mayo, PE C3D 2014, RD 2014 Win 7 64, Core i7, 6 GB RAM, Quadro FX 1700