Modeling: "Clone" functionality for the Edge Slide tool

In a certain 3D app there's this slide tool that slides edges and vertices just like in Blender, but additionally there's an option (checkbox) that can be activated in his tool settings (or by holding the ctrl key) called "Clone", and it works with edges only. What it does is, instead of sliding the selected edges, it clones them and slides, leaving the original selected edges intact. It's a very, very powerful concept. So it would be amazing to have that functionality in Blender's edge slide tool.

Note: If this can be done already please someone let me know. 😀 Thanks.

Quick example: